Fudgy brownies layered with the best brown butter cookies. This recipe combines a rich brown butter cookie dough with a decadent brownie batter, topped with chocolate chunks, for an irresistible dessert.
1. Make the cookies first: Brown butter and let cool slightly. Whisk with sugars with the browned butter until glossy, then add eggs and vanilla. Sift in the dry ingredients until just combined, then fold in chocolate. Chill for at least 1 hour.
2. Preheat oven to 350°F (175°C) and line an 8x8 pan with parchment.
3. Make brownie batter: Melt butter with chocolate chips, whisk in olive oil and cocoa powder. In another bowl, whisk sugars, eggs, and vanilla. Combine with chocolate mixture, then fold in flour until just mixed.
4. Assemble: Pour half the brownie batter into the pan and spread evenly. Add chunks of cookie dough across the surface (don’t cover fully). Pour remaining brownie batter over top, then finish with more cookie dough pieces pressed lightly on top. Lastly, top with the chocolate chunks to your liking.
5. Bake for 30–40 minutes, until edges are set and center is slightly soft. A toothpick should come out with moist crumbs, not wet batter.
6. Cool completely before slicing (this is key for clean layers).
