Preparation 20 min
Cooking time 35 min
- Adjust oven rack to the middle position and preheat to 350 °F (180 °C). Line a 9 by 13 by 2-inch aluminum baking pan with foil to cover the bottom and letting it hang over two sides. Grease lightly with cooking spray.
- In a stainless-steel pot, melt butter over medium-low heat. Once it has completely melted, increase the heat to medium and bring to a simmer, stirring while the butter cooks until it is golden yellow and stops sizzling. Remove from the heat and stir in dark chocolate. The mixture will seem quite thin. Set aside to cool.
- To make the brownie batter, combine white sugar, brown sugar, salt, eggs, and vanilla in a mixing bowl. Using the whisk attachment, whip on medium-high speed for about 8 minutes until it is extremely thick and fluffy.
- Meanwhile, sift together the flour and cocoa powder. When the eggs are fluffy and thick, reduce the mixing speed to low and pour in the warm chocolate-butter mixture. Once it is well mixed, add the flour and cocoa powder and mix until just combined. Use a spatula to scrape the bottom and sides of the bowl to ensure it is well mixed.
- Pour half of the brownie batter into prepared pan. Then cover the entire surface with squares of Lindt chocolate. Spread hazelnut cocoa spread over the chocolate pieces before pouring the remaining half of the batter on top. Smooth the top with a spatula and bake for about 30 minutes until the brownies are glossy and just barely firm.
- Allow the brownies to cool at room temperature before removing from the pan and cutting.
- Store at room temperature in an airtight container with wax paper between the layers for up to 1 week.