Brown Butter Oreo Brookies

Ingredients

• [Cookie layer] 110g browned butter
• [Cookie layer] 100g brown sugar
• [Cookie layer] 50g granulated sugar
• [Cookie layer] 1 large egg
• [Cookie layer] 1½ teaspoons vanilla extract
• [Cookie layer] 165g all-purpose flour
• [Cookie layer] ½ teaspoon baking powder
• [Cookie layer] ½ teaspoon salt
• [Cookie layer] 185g chocolate chips
• [Cookie layer] 1 cup chopped Oreos, about 8 biscuits
• [Brownie dry ingredients] 120g all-purpose flour
• [Brownie dry ingredients] ½ teaspoon baking powder
• [Brownie dry ingredients] ½ teaspoon salt
• [Brownie dry ingredients] 43g unsweetened cocoa powder
• [Brownie dry ingredients] 1 teaspoon instant espresso powder, optional
• [Brownie melted mixture] 170g butter
• [Brownie melted mixture] 28g vegetable oil
• [Brownie melted mixture] 67g granulated sugar
• [Brownie egg mixture] 200g granulated sugar
• [Brownie egg mixture] 2 large eggs
• [Brownie egg mixture] 1 egg yolk
• [Brownie egg mixture] 2 teaspoons vanilla extract
• [Assembly] ½ cup chopped Oreos, plus more for the top

Method

1. Heat the oven to 177°C/350°F. Line a 23cm/9-inch square tin with parchment.
2. For the cookie layer, mix the browned butter, brown sugar and granulated sugar. Beat in the egg and vanilla.
3. Fold in the flour, baking powder and salt, then the chocolate chips and 1 cup chopped Oreos.
4. Press the cookie dough evenly into the lined tin.
5. For the brownie layer, whisk the flour, baking powder, salt, cocoa and optional espresso powder together.
6. Melt the butter with the vegetable oil and 67g sugar over medium heat, then set aside.
7. In another bowl, beat the remaining 200g sugar, eggs, egg yolk and vanilla for 3–5 minutes.
8. Mix in the warm melted-butter mixture, then fold in the brownie dry ingredients and ½ cup chopped Oreos.
9. Spread the brownie batter over the cookie layer and scatter with more chopped Oreos.
10. Bake for 30–35 minutes.
11. Cool in the tin for at least 1 hour before slicing into 16 pieces.