Chocolate Kahlua Trifle

1 (17 ounce) package frozen Pepperidge Farm 3-layer fudge
    cake with chocolate frosting
1/2 cup chopped walnuts
8 ounces whipped topping
1 small box instant chocolate pudding, prepared with 2cups milk
1/2 to 1/3 cup Kahl?a

Cut the cake into 4 sections, then cut each section into 4 slices. In a trifle bowl or glass bowl, make the layers as follows: cake, Kahl?a (sprinkle over cake), pudding, whipped topping  and walnuts. Continue the layers until ingredients are used up, ending with whipped topping and walnuts. Cover with plastic wrap and refrigerate until serving time.

May be made ahead.