Key Lime Trifle

Heat oven to 350°F (or 325°F for dark or nonstick pan). Mix, bake and cool cake as directed on cake mix box using 13x9-inch pan. Cut cooled cake into about 3/4-inch pieces; set aside.

In large bowl, beat condensed milk and lime juice with whisk until well combined. In chilled medium bowl, beat whipping cream with electric mixer on high speed until medium to stiff peaks form. Using rubber spatula, gently fold whipped cream into condensed milk-lime mixture until smooth. Cover; refrigerate until needed.

Using food processor, process granola bars until ground.

Gently stir lime peel into whipped topping (do not overmix). Set aside.

In 3-quart glass trifle bowl, spoon layer of lime-cream mixture. Follow with layers of ground granola bars, chopped white chocolate and cake pieces. Repeat layers, leaving room for final layer of whipped topping. If desired, garnish with additional ground granola bar and Key lime slices. Cover; refrigerate at least 1 hour before serving.