Milky Swirl Brownies

Yield: 24 brownies

These rich, almost creamy brownies are an amazing treat for chocolate lovers. The condensed milk lightly caramelizes at the brownie edges during baking. You might not want to share those delicious edges—we won’t tell.

Ingredients

  • 12 oz. (24 Tbs.) unsalted butter; more for the pan, softened
  • 4-1/2 oz. (1 cup) all-purpose flour
  • 4 oz. (1-1/3 cups) Dutch-process cocoa
  • 6 oz. bittersweet chocolate, roughly chopped
  • 16 oz. (2-1/4 cups) granulated sugar
  • 2 oz. (1/4 packed cup) light brown sugar
  • 1-3/4 tsp. kosher salt
  • 6 large eggs, cold
  • 1 Tbs. pure vanilla extract
  • 1 tsp. instant espresso powder (optional)
  • About 1-1/4 cups Quick Homemade Condensed Milk

Preparation

  • Position a rack in the center of the oven and heat to 350°F. Line a 9×13-inch baking pan with parchment or aluminum foil, leaving an overhang on the longer sides, and butter lightly.
  • In a small bowl, sift together the flour and cocoa powder.
  • In a medium stainless-steel saucepan, melt the butter over medium-low heat. Increase the heat to medium and simmer, stirring with a heat-resistant spatula, while the butter hisses and pops. Continue cooking, scraping up any brown bits that form at the bottom of the pan, until the butter is golden yellow. Remove from the heat and stir in the chocolate; the mixture will seem thin.
  • In the bowl of a stand mixer fitted with the whisk attachment, combine the sugars, salt, eggs, vanilla, and espresso powder, if using. Whisk on medium-high speed until thick and fluffy, scraping down the bowl as needed, about 8 minutes. Reduce the speed to low and pour in the warm chocolate mixture. Once incorporated, fold in the flour mixture in thirds with a flexible spatula until well combined.
  • Pour the batter into the prepared pan, and smooth with an offset spatula. Use the back of a spoon to create 20 shallow indentations in the batter. Fill each with 1 Tbs. of condensed milk, then drag a butter knife through the milk and batter. Bake until the brownies are glossy and just barely firm, 25 to 30 minutes. Cool to room temperature. Use the parchment or foil overhang to lift the brownies from the pan, then cut into 24 pieces. Store in an airtight container for up to one week at room temperature.