Sarah's Reduced-fat Chocolate Fudge Cake Recipe

Directions:

1. FOR THE CAKE:.
2. Position a rack in the center of the oven and preheat to 350 degrees F; Grease and optionally dust with cocoa powder (best used with flouring chocolate cake pans), two 8-inch round nonstick cake pans; The batter is very soupy and will stick to the pans unless properly prepared.
3. Melt the chocolate squares over a double boiler or in the microwave; Don't allow any water droplets to get introduced into the chocolate while it's melting otherwise it might seize (not a pretty sight); Let cool until tepid.
4. In a medium bowl, using a handheld electric mixer, cream the butter and sugar together until it resembles coarse bread crumbs, and scraping down the sides of the bowl often, about 2 minutes; Beat in melted chocolate; Add the buttermilk, eggs, egg whites and beat until smooth; I found that a food processor works well for this step.
5. In a medium bowl, whisk together the flour and cocoa until well combined; (if the cocoa is lumpy, sift it, after measuring, onto a piece of waxed paper); With a large mixing spoon, add the flour mixture into the wet ingredients, scraping down the bowl often; Mix until smooth; With a cup held over the mixing bowl, dissolve the baking soda in a cup of hot coffee; The mixture will bubble up and may spill; Add to the batter and mix until smooth; The batter will be very thin; Divide it equally between prepared pans.
6. Bake until the cakes begin to pull away from the sides of the pans, about 30 minutes; The tops should still be shiny; Do not overbake; Do not open the oven until the last 5 minutes of baking; Cool in the pans on wire cake rack for 10 minutes; Invert onto racks.
7. Turn right side up and cool completely.
8. Place one cake, flat side up, on a serving platter; Spread with 1/3 of the Fudge Frosting; Frost the top and sides of the cake with the remainder and serve.
9. FOR THE FROSTING:.
10. Melt the chocolate squares (1 minute on high power in the microwave); Let cool until tepid.
11. Beat together ingredients (food processor works well); If this is too runny or dry, add sugar or milk to correct; Best used when applied to the cake at room temperature.
12. ADDITIONAL CHEF NOTES:.
13. For the cake, Sarah recommends using the sour cream as she says the result is moister; I used powdered buttermilk prepared in plain nonfat yogurt and was very pleased with the outcome.
14. I had good results using 1 whole stick of light butter in place of 1/2 stick full-fat butter; I also whizzed up about 3 T of oatrim in with the liquid ingredients; Oatrim is hydrolyzed oat bran, and it's useful for helping to retain that oh-so-yummy fatty mouthfeel in reduced-fat baked goods.
15. I didn't have bittersweet chocolate, and didn't feel like making a run to the store, so when I made this the other day, I used dark chocolate in the cake and semi-sweet chocolate chips in the frosting; worked great!
16. I ended up using some xanthan gum (1/4 tsp) to thicken the frosting as I didn't want to add too much sugar; I recommend adding half the called-for amounts of liquid to the frosting, and then slowly adding more.
17. When I prepared this, I doubled the cake recipe and the yield was 24 cupcakes plus 1 small rectangular cake prepared in an 8x4 loaf pan.