Classic Blondie-Brownie Swirl (Imperial Version)

1.Preheat your oven to 350°F (175°C). Grease and line a 2-liter cake mold with parchment paper, leaving some overhang for easy removal later.

2.In a medium saucepan, melt 10.5 oz of unsalted butter over medium heat. Remove from heat and let cool slightly.

3.In a large mixing bowl, combine the melted butter and 28.2 oz of vanilla sugar. Whisk until well combined and slightly cooled.

4.Add the 6 eggs one at a time, whisking well after each addition until the mixture is smooth and glossy. Stir in 2 tsp of vanilla extract if using.

5.Sift in 3.5 cups of all-purpose flour and 1 tsp of salt into the mixture. Gently fold until just combined, being careful not to overmix. Set the blondie batter aside.

6.In another saucepan, melt the remaining 10.5 oz of unsalted butter with 21 oz of chopped milk chocolate over low heat, stirring until smooth and fully melted. Remove from heat and let cool slightly.

7.In a large mixing bowl, combine the chocolate mixture with 28.2 oz of vanilla sugar, whisking until smooth. Add the 6 eggs one at a time, whisking until fully incorporated after each addition.

8.Sift in 2.1 oz of cocoa powder and 1 tsp of salt, then fold in 3.5 cups of all-purpose flour until just combined, ensuring not to overmix the brownie batter.

9.Pour the blondie batter into the prepared cake mold, spreading it evenly. Then, dollop the brownie batter over the blondie layer in spoonfuls, and use a knife or skewer to swirl the two batters together, creating a marbled effect.

10.Bake in the preheated oven for 25-30 minutes, or until the edges are set and a toothpick inserted in the center comes out with a few moist crumbs. Avoid overbaking to maintain a fudgy texture.

11.Once baked, remove from the oven and allow to cool in the mold for about 15 minutes. Then, lift the blondie-brownie swirl out using the parchment overhang and let cool completely on a wire rack before slicing into squares.