Cream 1/2 cup softened butter and 3/4 cup packed brown sugar. Add 1 egg, 1 tablespoon milk and 1 teaspoon vanilla; beat well. Stir in 1 (6 ounce) package semi sweet chocolate chips. Spread in greased 9 x 9 x 2 baking pan, or onto a pizza pan. Bake at 350 degrees for 30 minutes. Cool and cut into bars.

If you use a pizza pan, you can decorate for parties.