Chewy & Fudgy Brown Butter Chocolate Chip Bar Cookies

The perfect chocolate chip cookie morphed into bar cookies with the gooey-ness of a brownie and crowned with a shiny, crisp lid over the top.
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Brown Butter Muscovado Chocolate Chunk Bar Cookies Recipe | DisplacedHousewife

Feeling excited about these Chewy & Fudgy Brown Butter Chocolate Chip Cookie Bars from The Cookie Book that need a spot on your table.

Picture the perfect chocolate chip cookie recipe that’s morphed into a thick bar with the chewy, gooey-ness of a brownie, heaps of caramel notes from the brown butter and muscovado and crowned with a shiny, crisp lid over the top.

Brown Butter Muscovado Chocolate Chunk Bar Cookies Recipe | DisplacedHousewife

These bar cookies come together in a flash and are perfectly suitable to nosh while watching Sex Education or jazzed up with some vanilla ice cream to end a beautiful meal.

You know the kind of meal where you went to the store and bought special ingredients and thought it would be nice to treat yourself? Yep, that meal. End it with this.

You can see all of the Brownie & Bar Cookie Recipes. Here are some of my favorites: Foolproof Crinkly Fudgy BrowniesUltimate Skillet Brookies (brownies + chocolate chip cookie’s baby), Vegan Peppermint BrowniesS’mores Cookie Bars, Chocolate Hazelnut Brownies and White Chocolate Fudge Brownies.

The Baker’s Guide to Measuring Flour

One of the biggest (and most common) mistakes in baking is how we measure flour. If you find yourself without a scale, see my top tips on how to properly measure flour for the perfect amount every time!

Brown Butter Muscovado Chocolate Chunk Bar Cookies Recipe | DisplacedHousewife

Brown Butter Chocolate Chip Cookie Bar Notes

  • Sizes Matters. If you use a larger or smaller pan be sure to adjust your bake time accordingly. Additionally, this was tested in a ceramic pan (Staub). If you use a metal pan check earlier for doneness as it could affect the bake time.
  • Muscovado. Is the most glorious of unprocessed sugars that is rich in molasses and caramel notes. It’s magical and makes everything it touches 1000 times better. BUT, it’s pricey. And sometimes hard to find. So, If you can, use muscovado. If you can’t find it or you can’t be bothered, sub in dark brown sugar.
  • Egg Yolk. Extra egg yolks make things chewy and fabulous. Freeze your pristine, leftover egg whites and make meringues…all the kids are doing it.
  • Oil. I highly recommend you get Sunflower Seed Oil. I often grab the one at Trader Joe’s. Other neutral oils (think veggie and canola) impart a strange flavor to baked goods that I’m just not into. Sunflower Seed is totally tasteless. In the best way possible.
  • The Cut. Cutting into bar cookies is tricky. You want to dig in as soon as it’s out of the oven, right? But the longer you let it cool, the easier it will be to cut and you’ll get the cleanest cut possible. If you have no restraint which is how I’ve greeted 2019, just grab a spoon and have at it. I won’t judge.
Brown Butter Muscovado Chocolate Chunk Bar Cookies Recipe | DisplacedHousewife

Electric Stand Mixer (I prefer the Artisan to the Professional)

Breville Handheld Mixer, this one has a bunch of speeds, dough hooks, whisks. I was never a fan of handhelds until I got this one!

Whisk, I love this whisk so much! The angles at the base really help you get into the corners when whisking

Bowls, these bowls are awesome for mixing, setting atop simmering water when melting chocolate and for weighing out ingredients before starting (if you’re so inclined!)

This confetti spatula from this set — it’s too cute!

Knife, love this chef’s knife with the white handle

My favorite Staub baking vessel!

Let’s make some badass brown butter chocolate chip cookie bars, shall we?

Brown Butter Muscovado Chocolate Chunk Bar Cookies Recipe | DisplacedHousewife

Grab My Favorite Cookie Tips for Perfect Cookies, make these Crinkly, Fudgy Brownie Cookies (they’re so good!) or try my favorite, S’more Cookie Bars!

Don’t forget all of my other favorite chocolate chip cookie recipes (in addition to these!): Salted Olive Oil Chocolate Chip, Brown Butter Chocolate Chip Cookies, Small Batch Mega Vanilla Chocolate Chip Cookies (no rest!), DO NOT sleep on these Espresso Chocolate Chip Cookies ☕️ and/or get all of the cookie recipes right here.

Rebecca Firth

Chewy & Fudgy Brown Butter Chocolate Chip Bar Cookies

The perfect chocolate chip cookie morphed into bar cookies with the gooey-ness of a brownie and crowned with a shiny, crisp lid over the top.
5 from 4 reviews
Print Save Rate
Prep Time: 18 minutes
Cook Time: 25 minutes
Course: Dessert
Cuisine: Cookies
Keyword: Brown Butter, Muscovado, Bar Cookies, Cookies
Servings: 15 Bar Cookies


  • 94  grams  unsalted brown butter  (about 8 tablespoons (113 g) unsalted butter before browning)
  • 1/3 cup (75 g) sunflower or grapeseed oil (or other neutral oil)
  • 2 tablespoons (30 g) milk (cold)
  • 1 tablespoon (13 g) real vanilla extract
  • 2 large eggs (cold)
  • 1 egg yolk (cold)
  • 1 cup (220 g) dark muscovado sugar (packed; can substitute regular brown sugar, light or dark)
  • 1/2 cup (100 g) granulated sugar
  • 1 1/2 cups (203 g) bread flour (can replace with purpose flour 1:1)
  • 1 1/2 cups (203 g) all-purpose flour (how to measure flour)
  • 1 teaspoon baking powder
  • 1 teaspoon baking soda
  • 1 teaspoon sea salt
  • 1 cup (170 g) dark chocolate (chopped or chocolate chips)
  • Sea salt flakes for dusting on top (optional)


  • Preheat your oven to 375°F (190°C). Grease an 8 x 11–inch (20 x 28–cm) casserole dish and line with parchment paper, letting the excess fall over the sides.
  • Place 8 tablespoons (113 g) butter in a small saucepan and melt over medium heat. Once melted, crank up the heat to medium high. Stand by, continuously stirring and watching. Small golden brown bits (milk solids) will start to settle on the bottom of the pan. Once this happens, take it off the heat and pour into a large bowl (that is heat safe).
    (For more details on browning butter, check out my How to Perfectly Brown Butter tutorial)
  • To the browned butter, whisk in the oil, milk and vanilla until well blended and slightly frothy, about 2 minutes. Add in the eggs and egg yolk, one at a time, making sure each addition is well blended before adding the next. Finally, whisk in the muscovado (or brown sugar), sugar, baking powder, baking soda and salt and continue whisking for about 1 minute more.
  • With a rubber spatula, stir in the flour and mix until barely blended. Add in the chocolate chunks and continue to blend until just combined and the chocolate is evenly distributed.
  • Pour the mixture into the prepared baking dish. Dampen your hands and gently press down so that it covers the bottom of the dish. Bake in the center of the oven for 25 minutes and golden brown. Set on a wire rack; the cookie bars will continue to bake and firm up as they cools. Sprinkle with flaky sea salt, if using. Let cool completely before cutting. These are great the same day as they’re made and equally dazzling the next.


Melted Butter

Yes, you can sub in melted butter for the brown butter, just start with 7 tablespoons (98 g) butter and then melt…you’ll have the perfect amount!

Why Cold Ingredients?

Since the butter will be warm (and we don’t want to sit around and wait for it to cool), I have you adding in oil, milk and *COLD* eggs. These things will quickly bring your butter to room temperature. Don’t change up this order.

Want More Cookie Tips?

Head over to My 10 Favorite Tips for Better Cookies!

Need a Brown Butter refresher? 

Check out my How to Make Perfect Brown Butter tutorial!
*This recipe originally appeared in The Cookie Book. Some of the weight measurements, the order of ingredients, as well as the instructions have been edited/updated. This recipe is also now mixed in one bowl instead of two (yay!). 
Thanks for baking with me! Please rate + comment this recipe and tag me on social @displacedhousewife #displacedhousewife so I can see your beautiful treats! xo


Leave a Comment & Rate this Recipe

I love your comments, reviews and questions! If you love this recipe, please rate it when you leave a comment. Star ratings 🌟🌟🌟🌟🌟 help people discover my recipes. Your support means a lot, I look forward to chatting with you!

Rebecca xox

Recipe Rating


  • Gwen February 17, 2021 at 11:54 AM

    5 stars
    I followed the recipe exactly, because, you know, YOU’RE the expert here! Soooo …. I am still trying to figure out if I love you or if I hate you……. they are soooo soooo soooo good!!!! So I love you now, but when my jeans don’t fit anymore, then I’ll hate you (haha JUST KIDDING)

    • Rebecca Firth February 17, 2021 at 6:28 PM

      Gwennnn!!! I am SO HAPPY you liked these!!! And you love me, of course!! ;)

      I’m working on a new recipe that will use a similar cookies base—stay tuned!! xox

  • Sue December 2, 2020 at 6:14 PM

    Can I only use one type of flour? Can I also reduce the amount of sugar?

    • Rebecca Firth December 2, 2020 at 7:17 PM

      Hi Sue! You can use one type of flour…as for reducing the sugar, I haven’t made it that way so I would be hesitant to recommend. Sugar sweetens but it also tenderizes a baked good. Let me know what edits you make as it may help others (if possible!). Please reach out with any more questions. Have fun!! xox

  • Donna Vaughn July 11, 2020 at 1:51 AM

    I just made these today and very disappointed. They were very dry. I’m very meticulous about measuring and didn’t make any substitutions. Love the Muscovado sugar.

    • Rebecca Firth July 11, 2020 at 2:05 PM

      Hi Donna! These aren’t dry at all, in fact they error on the side of being quite damp, like a blondie. Something had to have gone amiss during the mixing stage. Sorry it wasn’t a great experience for you!
      R xo

  • Sheri December 30, 2019 at 7:34 PM

    Hi! These look amazing! Any thoughts on substituting a gluten free flour (I tend to use Cup 4 Cup when baking)? Would it be 3 cups of that given the 1 1/2 cups each of bread flour and regular flour? Any suggestions would be welcomed! Thank you!!

    • Rebecca Firth December 31, 2019 at 4:01 AM

      Hi Sheri!!! I would replace the Cup 4 Cup for all of the flour if you want them to be completely gluten free. One tip I have for baking gluten free is that it takes the gf flour longer to absorb the moisture. Consider letting the batter sit for several hours (and up to overnight in the fridge) prior to baking for the best results. Has this helped?!?! Let me know…I’m happy to chat through this more! xoxo

  • ashley depriest June 26, 2019 at 7:36 PM

    Hi Rebecca. What percentage of dark chocolate do you recommend? I have a great Scharffen Berger bar but it is 99% cocoa. Would you use something closer to 70% or would 99% be okay? Thanks!

    • Rebecca Firth June 26, 2019 at 9:33 PM

      Hi Ashley! I wouldn’t use a chocolate like that for these unless you like unsweetened chocolate in your treats. I would go for something in the 60-70ish range. I hope you love them!! And that’s one of my fav chocolate brands!! xoxo

  • Alexandra February 2, 2019 at 4:46 PM

    These look so incredible! I think I’m going to make them for a Super Bowl Party we’re heading to tomorrow, but I was wondering what changes I should make to fit them in a 9×13 pan? Do you think I should I 1.5x the recipe?

    • Rebecca Firth February 2, 2019 at 5:54 PM

      Hi Alexandra! Thank you so much!! Umm, I have never doubled it…sometimes bar cookies get tricky that way. Do you have a pie dish? Or some other less conventional dish that might be closer in size? Otherwise, I would reduce the baking time so they don’t overbake. Does this help? xoxo

  • chloe January 22, 2019 at 9:21 AM

    Oooh!! YES!!! finally someone has said it – veggie and canola oil gives baked goods a weird aftertaste. I TOTALLY AGREE. I’m going to give sunflower seed oil a go. I haven’t had luck even with grapeseed or rice bran :( Fingers crossed it works out. (I won’t blame you if it doesn’t, because I’m guessing these bars will taste good anyway? haha)

  • Morgan January 18, 2019 at 7:28 PM

    The So Cal sunshine analysis is no joke!!! Oh…and these look amazeballs and they will be the next thing I make from your wonderful book! XOXO

    • Rebecca Firth January 19, 2019 at 6:21 PM

      NO JOKE!!!! I hope you do make them!!! xoxox

  • Karen Caccavo January 18, 2019 at 4:12 PM

    Curious about the bread flour in the recipe. Why use it? Is it important (I don’t stock it in my pantry and it’s a snow day!)

    • Rebecca Firth January 19, 2019 at 6:21 PM

      Hi Karen! I use it in lots of cookie/bar recipes…it gives some nice chewiness that I love. You can totally sub in ap flour…the texture will be different, but it will work. Let me know how it goes! xoxo

  • Anita January 18, 2019 at 3:25 PM

    Yummm!! These are amazing. I learned a super weird trick, I think from ATK, for slicing gooey things like brownies. Use a plastic knife! Like the cheesy, disposable kind. It’s weird, but it works.
    So much love to you, Rebecca!

    • Rebecca Firth January 19, 2019 at 6:20 PM

      Hi Ani!! I’m going to have to try the plastic knife tip — it sounds amazing. Who can ever wait that long?!?!?!

      Lots of love to you!

  • Janet January 18, 2019 at 10:52 AM

    I’ve got your book from the library but will have to purchase! Was just at the doctor and really, really have to cut back on baking and eating cookies! Also, last week I watched the first episode of Sex Education. Nearly fell off my chair and did a LOT of laughing out loud!

    • Rebecca Firth January 18, 2019 at 2:16 PM

      Hi Janet! I love that you got my book from the library…one of my most favorite places!! I get your baking dilemma as it’s all I do. ;) I love to bake so much that when I want to cut back I give away lots and lots of sweet treats!!! And omg, Sex Education — I can’t wait for the second season. It’s perfect.

      Have fun baking and Netflixing!!