Dark Chocolate Mocha Brownies

Dark chocolate is a favorite around our house, so these frosted brownies are a hit. I came up with this treat by reworking a recipe I've used for a long time. We have six children, and these brownies disappear so fast I sometimes wonder if I actually made a batch.
-Linda McCoy, Oostburg, Wisconsin
60 ServingsPrep: 20 min. Bake: 25 min. + cooling
Ingredients
- 2 cups packed brown sugar
- 1 cup butter, melted
- 3 eggs
- 1 tablespoon instant coffee granules
- 2 teaspoons vanilla extract
- 1 cup all-purpose flour
- 1 cup baking cocoa
- 1/2 teaspoon baking powder
- 1/2 teaspoon salt
- 6 ounces bittersweet chocolate, coarsely chopped
- FROSTING:
- 1/4 butter, melted
- 3 tablespoons sour cream
- 2 teaspoons vanilla extract
- 2-3/4 to 3 cups confectioners' sugar
- 2 ounces grated bittersweet chocolate
Directions
- In a large bowl, combine brown sugar and butter. Beat in eggs, one at
- a time. Add coffee and vanilla; mix well. Combine the flour, cocoa,
- baking powder and salt; gradually add to sugar mixture. Stir in
- chocolate.
- Spread into a greased 13-in. x 9-in. baking pan. Bake at 350° for
- 25-30 minutes or until a toothpick inserted near the center comes
- out clean. Cool on a wire rack.
- For frosting, combine the butter, sour cream and vanilla until