Brown Butter Muscovado Chocolate Chunk Bar Cookies

Feeling excited about 2019 and thinking these Brown Butter Muscovado Chocolate Chunk Bar Cookies from The Cookie Book need a spot on your table. Picture the perfect chocolate chip cookie 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. These come together in a flash and are perfectly suitable to nosh while watching Sex Education (who has watched this on Netflix?!?!?) 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.

I can’t take all of the credit for this Cookie Book generosity. My friends Adam & Ryan (Husbands That Cook) are coming up this weekend and wanted to do an Instagram Live of one of the Cookie Book recipes…and for those of you that don’t have the book yet, this is a great one to try. Quick, easy and celebratory, just how we need daily life to be (minus the quick). Husband’s have a book coming out in March, Husbands That Cook, and it’s beautiful and gorgeous and I think you should all preorder it now. They are creative and thorough and thoughtful and make the most dazzling and delicious food. They have a shindig at The Grove in LA this March to celebrate that I’ll be going to — I’d love to see you there too!

It has been dark and gloomy and raining for days on end here which has been positively glorious but I’ve decided that southern Californians are addicted to sunshine and when it’s withheld it’s like everyone is suddenly on Xanax. Walking around like zombies. And talking about how they don’t want to do anything and have no motivation and cancelling going anywhere ’cause the roads are slick. I’m not even exaggerating one word of any of this. It’s quite the spectacle but it can’t be helped. I’m shrugging as I roll over in bed.

Before We Get Started:

  • 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.

Let’s make some badass bar cookies, shall we?

Brown Butter Muscovado Chocolate Chunk Bar Cookies

Makes 15 Bar Cookies


  • 8 tablespoons (115 g) unsalted butter
  • 1 cup (210 g) dark muscovado sugar, packed
  • 1⁄2 cup (96 g) granulated sugar
  • 1⁄3 cup (79 ml) sunflower seed oil or other neutral oil
  • 2 large eggs, room temperature
  • 1 egg yolk, room temperature
  • 2 tablespoons (30 ml) milk, room temperature
  • 1 tablespoon (15 ml) real vanilla extract
  • 1 1⁄2 cups (204 g) bread flour
  • 1 1⁄2 cups (204 g) all-purpose flour
  • 1 teaspoon baking powder
  • 1 teaspoon baking soda
  • 1 teaspoon sea salt
  • 11⁄2 cups (180 g) dark chocolate, chopped
  • Sea salt flakes for dusting on top, optional


  1. 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.
  2. Put the butter in a medium saucepan and melt over medium heat. Once melted, crank up the heat to medium high. Continue stirring and look for small golden bits that will start to settle on the bottom of the pan. It will smell deliciously nutty and caramel-y. This should take around 3 to 5 minutes. Once this happens, take it off the heat and pour into a medium, heat-safe bowl to cool a bit.
  3. When cooled slightly, whisk in the muscovado, granulated sugar, oil, eggs, egg yolk, milk and vanilla until thoroughly blended.
  4. In another medium bowl, whisk together the bread flour, all-purpose flour, baking powder, baking soda and sea salt. Add this to the butter mixture and stir until barely blended. Add in the chocolate chunks and continue to blend until just combined and the chocolate is evenly distributed.
  5. 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. It will continue to cook and firm up as it cools. Sprinkle with sea salt flakes, if desired. Let cool completely before cutting. These are great the same day as they’re made and equally dazzling the next.
  6. Thank you so much for making these bar cookies! If you make them, please tag me @displacedhousewife #displacedhousewife #thecookiebook if you post them to social so I can see your gorgeous sweet treats!

On My Mind

  • Reading: Killers of the Flower Moon and I can’t put it down. I feel a wee late to the game on this one. But I highly recommend it.
  • Watching: Sex Education as mentioned above. LOVE. Schitt’s Creek has been around for awhile, but MAN is it hilarious.
  • Cookie Stuff: Was interviewed for this Food & Wine article: Six Genius Swaps for Your Best Cookie Ever. Totally biased but I think you should stop everything and read it.
  • Instagram: Saturday, January 16th I will be live making these bars — join us! Husband’s will be giving away a copy of The Cookie Book, so head over to their Instagram account @husbandsthatcook for more info!
  • Sharing + Caring: This is the last of three recipes that I’m sharing from The Cookie Book. The first was these Everything Chocolate Chip Cookies before the book came out (people have been omitting the puffed quinoa or getting frisky with puffed amaranth) and then over the holiday I shared the White Chocolate Fudge Brownies that you can easily de-holiday by omitting the cranberries + pistachios. I hope you’ve enjoyed your sampling of Cookie Book cookies. Thank you to everyone that has baked some cookies, shared them, bought The Cookie Book for themselves and/or gifted it to friends and loved ones — you truly made this past year the most amazing year ever. THANK YOU!
  • Coming Soon: Winter Citrus Poppyseed Muffins (and they’re FAB), Your Best Cookie Tips post, Sourdough Starter post, Caramelized White Chocolate Dust Brownie Cookies With Salted Chocolate German Buttercream (these are INSANE + a collaboration that Erin (Cloudy Kitchen) and I did for a Cherry Bombe shindig late last fall. Erin is the buttercream master — it was so fun creating this cookie!!! Erin, I swear, this is happening stat!!! So excited to share all of these…and always open to requests…so email or comment below.

Heaps of love + light to you!

R xoxo



  • Alexandra 2019/02/02 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 2019/02/02 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 2019/01/22 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 2019/01/18 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

  • Karen Caccavo 2019/01/18 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 2019/01/19 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 2019/01/18 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 2019/01/19 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 2019/01/18 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 2019/01/18 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!!


Leave a Comment