Added 10/Sep/2014
source: smittenkitchen.com
Make the cake: Preheat the oven to 325°F. Line the bottom of a 9-inch round cake pan with parchment, and either butter and lightly flour the parchment and exposed sides of the pan, or spray the interior with a nonstick spray. In a large bowl, on the medium speed of an electric mixer, cream the butter until smooth. Add the sugars and beat until fluffy, about 3 minutes. Add the egg and yolk and beat well, then the red wine and vanilla. Don’t worry if the batter looks a little uneven. Sift the flour, cocoa, baking soda, baking powder, cinnamon and salt together, right over your wet ingredients. Mix until 3/4 combined, then fold the rest together with a rubber spatula. Spread batter in prepared pan. Bake for 25 to 30 minutes, or until a cake tester inserted into the center comes out clean. The top of the cake should be shiny and smooth, like a puddle of chocolate. Cool in pan on a rack for about 10 minutes, then flip out of pan and cool the rest of the way on a cooling rack. This cake keeps well at room temperature or in the fridge. It looks pretty dusted with powdered sugar.
Make the topping: Whip mascarpone, cream, sugar and vanilla together until soft peaks form — don’t overwhip. Dollop generously on each slice of cake. It can also be covered and refrigerated for up to 4 hours.