Melting Moments Bars

1 (18.25 ounce) box devil's food cake mix
1/4 cup water
2 eggs
1/4 cup soft butter or margarine
1/4 cup brown sugar
1/2 cup chopped nuts (optional)
3 squares sweetened chocolate (optional)

Mix together half of the cake mix with water, eggs, butter and sugar. Add remaining cake mix and blend in. Stir in nuts, if desired. Spread in greased jellyroll or 13 x 9-inch pan. Bake at 350 degrees F for 20 to 25 minutes. Melt chocolate squares and drizzle over top, if desired.