1Preheat oven to 350°F. Line an 8x8 inch pan with parchment paper.
2Prepare cookie layer: Mix flour, baking soda, and salt. Combine melted butter, brown and granulated sugar, egg, and vanilla. Whisk until smooth and fluffy (2-3 min). Add dry ingredients and chocolate chips. Mix until just combined.
3Prepare brownie layer: Make browned butter by melting butter in a saucepan over medium-low heat, stirring until foamy (6-8 min). Continue until milk solids are golden brown and smell nutty. Transfer to a heatproof bowl. Add cocoa powder, oil, vanilla, and chopped chocolate; mix until smooth. Whisk 3 eggs and light brown sugar (5-6 min) until dissolved. Add powdered sugar and mix (1-2 min). Add cooled browned butter mixture; mix until smooth. Add flour and chocolate chips; mix until well combined.
4Layer cookie and brownie batters in the prepared pan.
5Bake for 50-55 minutes or until edges are golden and center is a little fudgy.
6Let cool completely before cutting into brookies.
Ingredients
0.5 cups unsalted butter, melted and cooled
0.5 cups light brown sugar
0.33 cups granulated sugar
1 large egg, room temp
1 tbsp vanilla extract
1.25 cups all-purpose flour, spooned and leveled
0.5 tsp baking soda
0.5 tsp flaky sea salt
1.5 cups semi-sweet chocolate chips
1 cup unsalted butter
0.5 cup Dutch-processed cocoa powder
1 tsp vanilla
0.5 cup light brown sugar, spooned and leveled
1.75 cup powdered sugar
0.75 cups semi-sweet chocolate chips
0.33 cups semi-sweet chocolate, chopped
3 eggs, room temp
0.5 cup all-purpose flour
1 pinch salt
3 tbsp olive oil
Equipment
8*8 inch baking panparchment paperwhiskspatulasaucepanglass bowl