Easy Caramel Cake
Make a butter recipe cake from a mix, according to package directions. Bake in a 9-by-13 pan. Allow to cool completely.
Melt 2 sticks butter in a heavy saucepan. Add 2 cups brown sugar and 1/2 cup milk. Mix together. Bring to a rolling boil. Boil 2 minutes, whisking constantly. Remove from heat and let sit for exactly 5 minutes. Whisk in 2 1/2 to 3 cups powdered sugar. (For best results, sift it first.) Stir until lumps are gone. Add 1 teaspoon vanilla. Pour over cooled cake. Slice and serve.