This is the very best of a delicious brownie and a cake! It is moist and chewy, but still not too heavy and the slightly bitter cake is perfectly balanced by the sweetness of the topping. Chopped berries are a perfect finish to this wonderful cake.
For the cake:
1/2 cup (1 stick) butter, cut into 1 inch pieces, plus more, room temp, for pan
3/4 cup + 2 tbs sugar, divided, plus more for the pan
10 oz semisweet* chocolate, coarsely chopped
2 tbs canola oil
6 large eggs
2 tbs unsweetened cocoa powder
1 tsp vanilla
For the topping:
1 cup chilled heavy cream
1/2 cup mascarpone
3 tbs powdered sugar
*This cake turns out tasting about the same bitterness as semi-sweet chocolate, but is nicely balanced by the topping. If you prefer something sweeter, use sweet chocolate.
Special equipment: 9 inch spring form pan
Preheat oven to 350F. Lightly butter the pan and dust with sugar.
Combine chocolate, oil and 1/2 cup butter in a large heatproof bowl and set over saucepan of simmering water. Stir often until chocolate is melted.
Meanwhile separate 4 eggs, placing whites and yolks in separate medium bowls. Add cocoa powder, vanilla, 1/4 cup sugar and remaining 2 eggs to the yolks and whisk until the mixture is smooth. Gradually whisk the yolk mixture into the melted chocolate mixture.
Beat the egg whites with an electric mixer on high until frothy. Gradually beat in 1/2 cup sugar and beat until stiff peaks form. Gently fold egg whites into chocolate mixture in 2 additions, folding until just incorporated. Scrape into prepared pan. Smooth the top and sprinkle with remaining 2 tbs sugar.
Bake until top is puffed, starting to crack and cake is pulling away from the edge, about 35-45 mins. Let cool completely in pan on a wire rack. Cake will collapse in the centre and crack further as it cools. Cake can be made 1 day ahead. Cover in pan and store airtight at room temperature.
With an electric mixer, beat mascarpone, cream and powdered sugar on medium speed until soft peaks form. Remove sides of springform pan from the cake. Mound whipped cream mixture in centre of the cake and serve.
Recipe from Bon Appétit