Gabi's Favorite Fudge Cake, makes one 9 inch -two layer cake -can be doubled. 

3 ounces unsweetened chocolate, melted and cooled
2 Cups sifted all purpose flour (plus more for pans)
2 teaspoons baking soda
1/2 teaspoons salt
2 Tablespoons cocoa powder, sifted for lumps
1/2 Cup (1/4lb) butter, softened to room temperature (plus more for pans)
2-1/4 Cups light brown sugar, firmly packed
3 eggs, room temperature
2 teaspoons Vanilla extract
1 Cup sour cream
1 Cup boiling water

Preheat oven to 350F.
Butter and lightly flour two 9inch round cake pans, place a parchment circle that has been cut to fit the bottom 
in each round and butter and flour the parchment.

Sift flour, soda, salt and cocoa together in small bowl. In the bowl of a stand mixer with the paddle attachment,
or in a large bowl with a hand mixer, beat butter until soft. Add brown sugar and eggs and beat at high speed
until light and fluffy, approximately 3 minutes. Beat in vanilla and melted, cooled chocolate. Stir in dry ingredients
alternately with sour cream, beating slowly but well until incorporated after each addition. Add boiling water and 
stir until batter is evenly thin. Pour at once into prepared pans and bake at 350F for 35 minutes or until
top springs back when lightly touched. Cool in pans 5 minutes on wire racks and then run a straight spatula
around the sides and remove to rack, paper side down, to cool completely.