Crunchy-Top Gingerbread

1 package (14-1/2 ounces) gingerbread mix
1/4 cup packed brown sugar
2 tablespoons all-purpose flour
2 tablespoons butter or margarine
1/8 teaspoon salt
1 teaspoon ground cinnamon
1/2 cup chopped walnuts
Whipped topping, optional

Prepare gingerbread according to package directions. Bake in a greased 11-in. x 7-in. baking pan at 350° for 25 minutes. Meanwhile, in a mixing bowl, combine brown sugar, flour, butter, salt, cinnamon and nuts; mix well.

Sprinkle over gingerbread; bake for an additional 10 minutes. Cut into squares and serve warm. Garnish with dollop of whipped topping if desired. Makes 12-15 servings.