Prepare the cake mix to make 8-inch or 9-inch layer cakes (2 per mix). Follow directions to remove from pans and fully cool (especially if gluten-free). Note: cake layers may be wrapped in plastic wrap and chilled before proceeding for easier cutting and frosting._
Cut a 3 ½ inch hole in the center of one layer of the cake (I used the rim of a large glass as a guide).
Place the layer with a hole on top of a second layer aligning the sides to have the layers directly underneath each other. Cut a hole in the second cake.
Place an uncut layer of cake on a serving plate or cake cardboard.
Spread a layer of frosting on the bottom side of one of the cut layers of cake and place it on top of the bottom layer.
Repeat with the second cut layer, aligning it so the holes are directly above each other.
Fill the hole with the assorted Easter candy.
Spread a layer of frosting on top of the third layer and place the last layer on top.
Frost the outside of the cake and decorate the top. Chill fully for the best slicing.
Note: To place a large chocolate bunny on the top of the cake as shown in the photos, I inserted toothpicks into the bottom of the bunny to stablize it on top of the cake: