Using a sharp paring knife, gently cut the length of the pod so that it's split down the middle. Don't worry if you cut through the pod, it's fine. Place the pods in the jar and cover with your preferred alcohol (bourbon is my favorite). Seal the jars and store out of direct sunlight. Periodically give the jar a gentle shake to mix things up. You can start using your vanilla extract after 2-3 months, but ideally you'll taste the true beauty of your extract closer to 6-12 months. You'll know it's ready once the color has deepened, the aroma is rich and the taste is a slice of heaven in your baked goods.