Ingredients:
3 squares unsweetened chocolate
2¼ cups sifted cake flour
2 teaspoons baking soda
½ teaspoon salt
½ cup soft butter
2½ cups light-brown sugar, firmly packed
3 eggs
2 teaspoons vanilla
½ cup buttermilk
1 cup boiling water
Melt chocolate over hot (not boiling) water; cool. Preheat oven to 350º. Grease & flour 3 8" cake pans or 2 9" pans.
Sift flour with baking soda & salt, set aside. Beat butter & brown sugar; add eggs, one at a time, then vanilla, beating well after each addition. Mixture should be very light & fluffy (beat with mixer at high speed for about 5 minutes). Add chocolate gradually. Add flour, in quarters, alternating with buttermilk, in thirds, beginning & ending with flour. Stir until just blended. Stir in water until just smooth.
Turn into pans. Bake at 350º for 30-35 minutes. Let cool in pans on rack for 10 minutes. Remove from pans & cool completely on racks.