Betsy'S Chocolate Fudge Cake
["3 sq. unsweetened chocolate", "2 1/4 c. sifted flour", "2 tsp. baking powder", "1/2 tsp. salt", "1/2 c. butter", "2 1/4 c. packed light brown sugar", "3 eggs", "1 1/2 tsp. vanilla", "1 c. sour cream", "1 c. boiling water"]
["Melt chocolate in small bowl over hot water; cool.", "Grease and flour 2 to 3 (9-inch) cake pans.", "Sift flour, baking soda and salt onto wax paper.", "Beat butter until soft in large bowl.", "Add brown sugar and eggs; beat with mixer at high speed until light and fluffy (5 minutes).", "Beat in vanilla and chocolate.", "Stir in dry ingredients, alternating with sour cream.", "Beat well with wooden spoon after each addition.", "Stir in boiling water (batter will be thin).", "Pour into pan and bake at 350\u00b0 for 35 minutes. Cool pans on rack for 10 minutes; turn out on racks.", "Cool completely and ice with Chocolate Fudge Frosting."]
["unsweetened chocolate", "flour", "baking powder", "salt", "butter", "brown sugar", "eggs", "vanilla", "sour cream", "boiling water"]