Birthday Brookies

Preparation

1. Brownie Batter

   Step 1

   Preheat the oven to 350°F (177°C). Line a 13×9" metal baking pan with parchment paper, leaving a few inches of overhang on two opposite sides.

   Step 2

   In a large heat-safe bowl, whisk 12 Tbsp. unsalted butter, melted and hot (170 g), 3 Tbsp. vegetable oil, and 1½ cups granulated sugar (300 g). Let sit for 3–5 minutes to slightly cool. Whisk in 2 large eggs, at room temperature, 1 egg yolk, at room temperature, and 1½ tsp. vanilla extract. Mix well, then whisk in 1 cup unsweetened Dutch-process cocoa powder (84 g), ¾ cup all-purpose flour (94 g), 1 Tbsp. hot water, and ½ tsp. salt. The batter should be thick. Fold in 1½ cups semisweet chocolate chips (270 g), then spread the batter evenly in the prepared pan.

2. Cookie Dough

   Step 3

   In a large bowl using a handheld or stand mixer fitted with the paddle, beat 8 Tbsp. unsalted butter, at room temperature (113 g), ⅓ cup brown sugar (67 g), and ⅓ cup granulated sugar (67 g) on medium-high speed until the mixture is light and creamy, about 3 minutes. Add 1 large egg, at room temperature, 1 tsp. vanilla extract, and ¼ tsp. almond extract (if using), and beat on high speed until combined, about 1 minute. Scrape down the sides of the bowl as needed. Add 1¼ cups all-purpose flour (156 g), ½ tsp. baking powder, and ⅛ tsp. salt and beat on low speed until combined. Beat in ½ cup white chocolate chips (90 g) and ⅓ cup rainbow sprinkles (57 g). The dough should be thick and sticky.

   Step 4

   Press about ¼ cup (70g) of the cookie dough into a flat disk and place it on top of the brownie batter. Repeat with the remaining cookie dough, covering the surface of the brownie layer but leaving some chocolate parts exposed. Lightly press down on the cookie dough to make an even layer as best you can. Top with extra sprinkles, if desired.

   Step 5

   Bake for 32–36 minutes or until the top is lightly browned. If the top browns too quickly, loosely tent aluminum foil over the pan. Err on the side of underbaking, as the brookies continue to set as they cool. Cool the brookies completely in the pan set on a cooling rack.

   Step 6

   Lift the brookies out of the pan by gripping the parchment paper overhang; transfer to a cutting board and cut into squares.

   Step 7

   Do Ahead: Store covered tightly at room temperature for up to 1 week.