Malted Brownies

Preheat the oven to 325°F. Line an 8x8-inch metal baking pan with parchment paper, leaving an overhang, and spray with nonstick cooking spray.
In a small saucepan set over medium-low heat, melt the butter. Swirling the pan occasionally, continue to cook the butter, increasing the heat to medium. Swirl the pan until the butter develops a nutty aroma and brown bits start to form at the bottom. Once the bits are amber in color, remove from heat and pour into a large mixing bowl, scraping the brown bits into the bowl.
Using a rubber spatula, add the sugar to the hot browned butter and combine until a thick paste forms. Let cool until barely warm. Vigorously whisk in the eggs, egg yolk, and vanilla for about 30 seconds, or until very smooth. Whisk in the cocoa powder. With the spatula, fold in the flour, malt powder, cornstarch, and salt until combined. Stir in the chocolate chips. Batter will be very thick.
Spread the brownie batter evenly into the prepared pan. Place in the oven and bake for 30 to 33 minutes, or until the brownies are set and a cake tested inserted into the center has moist crumbs attached. Do not overcook, the brownies will set as they cool. Let cool completely before cutting into squares and sprinkling with sea salt if desired.
Brownies can be stored in an airtight container at room temperature for up to 3 days or in the fridge for up to 5 days. Serving chilled increases fudginess.