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This recipe is from my ICE pastry course curriculum, so it's by weight. It's a nice dense chocolate cake and easy to make. I used vanilla Italian meringue buttercream and fresh raspberries to layer it. Yum!

The Horseradish Grill's Chocolate Cake
1 lb sugar
6 oz AP flour
½ tsp salt
¾ tsp baking soda
4 oz unsweetened chocolate, cut into 1/4 inch pieces
8 fl oz hot water
2 eggs
4 fl oz vegetable oil
1 ½ tsp vanilla extract
¼ pint sour cream

Makes two 9” round cakes

1. Butter and line pans with parchment paper.
2. For the cake batter, in a mixing bowl, stir together the sugar, flour, salt and baking soda, and set aside. Place the cut up chocolate in a bowl and pour the hot water over it. Let stand while the chocolate melts and you are preparing other ingredients.
3. In mixing bowl, whisk the eggs until liquid, then whisk in the oil, vanilla and sour cream, one at a time. Whisk the chocolate and water mixture smooth and scrape it into the egg mixture; whisk smooth.
4. Fold a third of the flour mixture in the chocolate batter. Repeat until all the dry ingredients are incorporated.
5. Divide the batter between the prepared pans and smooth the tops. Bake the cake at 325 degrees for about 30 to 40 minutes, or until well risen and a toothpick inserted into the center emerges clean. Cool the cakes in pans on racks for 5 minutes, invert each onto a rack, peel off paper and invert again onto other racks to cool right side up.

You can use it almost any place you use regular cocoa powder. Just sub out 1 oz of the baking chocolate for every 3 tbsp cocoa called for in a recipe.

I like this icing:
Mexican Chili frosting (Food Network Recipe)
* 1 (8-ounce) package cream cheese, at room temperature
* 1/2 cup (1 stick) unsalted butter, at room temperature
* 1 teaspoon chili powder
* 1/2 teaspoon ground cinnamon
* 1/4 teaspoon salt
* 1 teaspoon vanilla extract
* 3 cups confectioners' sugar, sifted
* 3 ounces unsweetened chocolate, melted
cream the cream cheese and butter together thoroughly. Add the chili power and cinnamon, mixing to incorporate. Add the salt, vanilla, and confectioners' sugar. Finally, mix in the melted chocolate and blend thoroughly until smooth. If additional thickening is needed, add more sifted confectioners' sugar, a little at a time, until a spreadable consistency is reached.

These Ina Garten Brownies are pretty darn good too.
* 1 pound unsalted butter
* 1 pound plus 2 cups semisweet chocolate chips, divided
* 6 ounces unsweetened chocolate
* 6 extra-large eggs
* 3 tablespoons instant coffee powder
* 2 tablespoons real vanilla extract
* 2 1/4 cups sugar
* 1 ¼ cups flour, divided
* 1 tablespoon baking powder
* 1 teaspoon kosher salt
* 3 cups diced walnut pieces

Directions

Preheat oven to 350 degrees F. Grease and flour a 13 by 18 by 1 1/2-inch sheet pan.

Melt together the butter, chocolate chips, and unsweetened chocolate on top of a double boiler. Cool slightly. Stir together the eggs, instant coffee, vanilla and sugar. Stir in the warm chocolate mixture and cool to room temperature.

Stir together the flour, baking powder and salt. Add to cooled chocolate mixture. Toss the walnuts and chocolate chips with flour to coat. Then add to the chocolate batter. Pour into prepared pan.

Bake for about 30 minutes, or until tester just comes out clean. Halfway through the baking, rap the pan against the oven shelf to allow air to escape from between the pan and the brownie dough. Do not overbake! Cool thoroughly, refrigerate well and cut into squares.