In a large bowl, combine the cake mix, milk, nuts and butter. Spread half into a greased 13-by-9-by-2-inch baking pan. Bake at 350 degrees for 13–15 minutes or until set. Place candies, cut side down, over crust; top with remaining cake mixture. Bake 25–30 minutes longer or until golden brown. Cool on wire rack. Cut into bars.