Description
These brown butter brookies layer a nutty chocolate chip cookie dough and a fudgy brownie batter in one pan for chewy, gooey squares with crinkly tops—an easy, crave-worthy dessert that feels bakery-special at home.
Ingredients
For the Brown Butter Cookie Layer:
1 cup (226 g) unsalted butter, browned and cooled until warm
1 cup (200 g) packed light brown sugar
1/2 cup (100 g) granulated sugar
2 large eggs, room temperature
2 teaspoons pure vanilla extract
2 1/4 cups (280 g) all-purpose flour
1 teaspoon baking soda
1/2 teaspoon baking powder
3/4 teaspoon fine sea salt
1 1/4 cups (210 g) semisweet chocolate chips or chunks
For the Fudgy Brownie Layer:
1/2 cup (113 g) unsalted butter, browned or melted
3/4 cup (150 g) granulated sugar
1/2 cup (100 g) packed light brown sugar
2 large eggs, room temperature
1 teaspoon pure vanilla extract
1 teaspoon espresso powder (optional, boosts chocolate)
1/3 cup (40 g) unsweetened cocoa powder
3/4 cup (95 g) all-purpose flour
1/2 teaspoon fine sea salt
3/4 cup (135 g) chocolate chips or chunks
To Finish:
Flaky sea salt, for sprinkling
Instructions
1. Preheat oven to 350°F (175°C). Line a 9×9-inch pan with parchment, leaving overhang; lightly grease.
2. Brown 1 cup butter for the cookie layer; cool until warm and fluid.
3. Whisk warm brown butter with brown and granulated sugars until glossy.
4. Whisk in eggs and vanilla for 30 seconds.
5. Fold in flour, baking soda, baking powder, salt, and chocolate chips; do not overmix.
6. For brownie batter, whisk 1/2 cup butter with both sugars until combined.
7. Add eggs and vanilla; whisk 1–2 minutes until slightly thick and pale.
8. Whisk in espresso powder (optional) and cocoa.
9. Fold in flour and salt just until no dry streaks remain; stir in chocolate chips.
10. Press 2/3 of cookie dough into pan. Dollop half the brownie batter over top.
11. Add remaining cookie dough in spoonfuls, then dollop remaining brownie batter.
12. Swirl gently with a knife 3–4 times; do not fully mix.
13. Bake 28–34 minutes until edges are set and a toothpick shows moist crumbs.
14. Sprinkle flaky sea salt. Cool at least 45 minutes, then lift and slice into 16 squares.
Notes
Cool brown butter to warm before mixing to prevent greasy dough.
For shinier brownie tops, whisk eggs and sugar a full 1–2 minutes.