1 (18.25 ounce) package yellow cake mix
1 (8 ounce) package raspberry flavored Jell-O mix
8 fluid ounces raspberry flavored lemon-lime flavored carbonated beverage
1 cup hot water
Prepare and bake cake according to package directions. Bake as directed on package. Cool completely.
Using a very sharp knife, cut into ΒΌ inch squares about 3 inches wide. Place squares 1 cup at a time on the filling of a jelly roll pan. Help with handles of jelly-roll pan if necessary.
Combine with raspberry jelly filling and hot water.
Drop raspberry jelly filling from a wire pan onto raspberry jelly filling.
Gently press jelly-roll pan seam to seam; flatten cake. Cover and chill overnight.
Remove from refrigerator and let cool completely. Refrigerate to chill 3 hours before carving.