Best Fudge Cake

3 ounces baking chocolate
1/2 cup butter
2 1/4 cups light brown sugar
3 eggs
1 1/2 teaspoons vanilla
2 teaspoons baking soda
1/2 teaspoon salt
2 1/4 cups sifted cake flour
1 cup sour cream
1 cup boiling water

In a large mixer bowl, cream butter until smooth. Add brown sugar and eggs. Beat with mixer till light and fluffy, about 5 minutes With mixer on low speed, beat in vanilla and chocolate, then baking soda and salt. Add flour alternately with sour cream, beating on low speed until smooth. Pour in boiling water; stir with spoon until blended. Pour into greased and floured pan(s). Bake 35 minutes at 350�F or until done. Makes one 9 - 13" pan or one 2-layer 9" round cake.