Fresh Milled Sourdough Brookies
These Fresh Milled Sourdough Brookies combine two classic desserts into one irresistible bar. A rich, fudgy brownie layer made with freshly milled flour and sourdough starter is topped with a soft and chewy chocolate chip cookie layer for the ultimate crowd-pleasing treat. Perfect for potlucks, family gatherings, bake sales, or whenever you can't decide between brownies and cookies, these brookies deliver the best of both worlds in every bite. The fresh milled flour adds depth of flavor, while the sourdough starter enhances the texture and creates a rich, bakery-style dessert everyone will be asking for again.
Equipment
- 1 9x13-inch pan (I prefer stainless steel)
Ingredients
Chocolate Chip Cookie Layer
Fresh Milled Flour
- 135 g + 2 tablespoons fresh milled soft white flour (1 cup)
Dry Ingredients
- ¾ teaspoon arrowroot powder or cornstarch 2g
- ½ teaspoon baking soda 2g
- Pinch of salt
Wet Ingredients
- 6 tablespoons unsalted butter softened (85g)
- ½ cup packed brown sugar 107g
- 2 tablespoons granulated sugar 25g
- 1 large egg yolk
- ¾ teaspoon vanilla extract 4g
- 3 tablespoons active sourdough starter 45g
Mix-Ins
- ¾ cup semi-sweet chocolate chips 128g (reserve 1/4 c for topping)
Brownie Layer
Fresh Milled Flour Blend (100g total), about ¾ cup fresh milled flour
- 50 g soft white wheat berries
- 50 g hard white wheat berries
Dry Ingredients
- ⅓ cup unsweetened natural cocoa powder 28g
- ½ teaspoon salt 3g
Wet Ingredients
- ½ cup butter 113g
- 1¼ cups granulated sugar 248g
- 2 large eggs
- 1 large egg yolk
- 1 teaspoon vanilla extract 5g
- ¼ cup active sourdough starter 60g
Mix-Ins
- ¼ cup semi-sweet chocolate chips 43g
Instructions
Make the Cookie Dough
Cream the Butter and Sugars
- In a large mixing bowl, beat softened butter, brown sugar, and granulated sugar until light and creamy, about 2–3 minutes.
Add the Wet Ingredients
- Beat in the egg, vanilla extract, and sourdough starter until smooth and fully incorporated.
Add the Dry Ingredients
- Mix in flour, cornstarch, baking soda, and salt just until combined.
Fold in the chocolate chips.
Rest the Dough
- Cover and let rest at room temperature for 20–30 minutes, or refrigerate while preparing the brownie layer.
- Resting allows the fresh milled flour to fully hydrate for a softer cookie topping. (You can also ferment overnight)
Prepare the Sourdough Brookie Pan
- Line a 9x13-inch baking pan with parchment paper, leaving overhang for easy removal.
Melt Butter and Chocolate
- In a medium saucepan over low heat, melt the butter and chocolate chips together, stirring until smooth.
- Remove from heat.
Add Sugar and Eggs
- Whisk in granulated sugar.
- Add eggs and egg yolk one at a time, whisking well after each addition.
- Whisk in vanilla extract and sourdough starter until fully smooth.
Add Dry Ingredients
- Fold in flour, cocoa powder, and salt just until combined.
- Do not overmix.
Preheat oven to 350°F (177°C).
Rest the Batter
- Let the brownie batter rest for 10–15 minutes to hydrate the fresh milled flour.
Assemble the Brookies
Spread the Brownie Layer
- Pour brownie batter into the prepared pan and spread evenly.
Scoop the Cookie Dough
- Using a 1 tablespoon cookie scoop, portion cookie dough evenly over the brownie layer.
- This should give approximately 8 scoops.
- Gently flatten each scoop slightly with your fingertips or the back of a spoon to help the dough spread evenly while baking.
Bake
- Bake for 20 minutes, or until:
- The cookie layer is lightly golden
- The edges are set
- A toothpick inserted near the center comes out with moist crumbs
- If browning too quickly, loosely tent with foil during the final 10 minutes.
Cool and Slice
- Cool completely in the pan.
- For the cleanest slices, chill for 30–60 minutes before lifting from the pan and cutting.
Notes
