CAKE:

1 c. butter, softened
1 c. firmly packed brown sugar
2/3 c. sugar
2 tsp. vanilla extract
1/2 tsp. salt
4 eggs
2 c. all-purpose flour
1 (12 oz.) pkg. (2 c.) Nestle Toll House Little Bits semi-sweet chocolate, divided

FROSTING:

3/4 c. butter, softened
1 1/2 c. sifted confectioners' sugar
2 tsp. vanilla extract

CAKE: Preheat oven to 350 degrees. Grease 15 1/2 x 10 1/2 x 1 inch baking pan. Line with waxed paper. In bowl, cream butter, brown sugar, sugar, vanilla extract and salt. Add eggs, one at a time, beating well after each addition. Gradually add flour. Stir in 1 cup Little Bits semi-sweet chocolate. Spread into prepared pan.

Bake at 350 degrees for 20-25 minutes. Cool completely. Loosen sides of cake. Invert onto lightly floured cloth. Peel off waxed paper. Cut cake crosswise into 4 (3 3/4 x 10 inch) sections. Spread 3 slightly rounded tablespoons frosting on one cake layer. Top with second layer. Repeat layers. Frost with remaining frosting.

FROSTING: Melt over hot (not boiling) water, 1 cup Little Bits semi-sweet chocolate; stir until smooth. (In microwave: melt on high 1 minute, stir; repeat.) Set aside. In bowl, cream butter and confectioners' sugar. Add melted chocolate and vanilla extract; blend until smooth. Makes 1 (10 inch) cake.