Creme fraiche is like sour cream, but better: rich, custardy, creamy, tart. We use it here to add vibrance and depth to this ethereally delicate chocolate sheet cake (and its silky sheath of frosting). Yum.
Chocolate Creme Fraiche Cake
Makes one 9×13-inch cake
2 cups granulated sugar
1 3/4 cups all-purpose flour
3/4 cup unsweetened cocoa powder
1 tsp baking soda
1/2 tsp salt
1 cup freshly brewed strong coffee
3 oz semisweet chocolate, roughly chopped
1 tbsp espresso powder
1/2 cup creme fraiche
1/2 cup canola oil
2 tsp pure vanilla extract
4 tbsp unsalted butter, softened
3/4 cup creme fraiche
2 1/2-3 cups confectioner’s sugar
1 tsp pure vanilla extract
1-2 tbsp whole milk
Preheat oven to 350 degrees Fahrenheit and butter a 9×13-inch cake pan. In medium-sized bowl, whisk together eggs, creme fruit, oil, and vanilla and set aside. Pour hot coffee over the chocolate, stirring until melted. Stir in the espresso powder and set aside. In a large mixing bowl, whisk together sugar, flour, cocoa, baking soda, and salt. Stir coffee mixture into dry ingredients. Stir creme fraiche mixture into the batter until just combined. Pour the batter into the prepared pan and bake for 25-30 minutes, until a tester comes out of the center of the cake clean, with moist crumbs. Transfer cake to a rack to cool completely before frosting.
Beat together butter and creme fraiche. Beat in confectioner’s sugar in 1/2 cup increments, alternating with the vanilla and the whole milk, until smooth and creamy. When the cake is completely cool, spread the top of the cake with frosting. Slice into squares and enjoy. Cake will last up to three days if kept refrigerated; simply remove from the refrigerator 30 minutes before serving.