A coworker made this and I wanted to duplicate for my mother-in-law's birthday. I made some changes because I know she doesn't have a huge sweet tooth. But the cake still turned out delish!
1 box yellow cake mix
1 cream cheese frosting (I use Pillsbury)
2 pints fresh strawberries
1 pint fresh blueberries
1/4 cup raspberry jam
40 Kit Kat pieces (the individual piece, not a "bar" and buy extra)
Preheat to 350 degrees. Make cake according to the box directions. This recipe will only use one 8 or 9 inch round cake. I used the rest for cupcakes. While the cake is cooking, clean strawberries and blueberries. I slice the strawberries so it is easier to eat (this is a deviation from the original recipe). Gently mix together and place in a bowl, cover with plastic rap and set aside.
When cool enough to remove from pan, place on a cooling rack. I gently cut the top to make it flat. Heat up raspberry jam, be careful not to burn. I used the microwave for about 30 seconds. With a pastry brush, spread the hot jam on the top of the cake. If you do this while it is warm, it will soak in nicely. (This step is a deviation from the original recipe.)
When cake is finally cooled, place on a flat plate with enough of an edge to line the cake with Kit Kats. On the edge of the cake only, spread with the cream cheese frosting. While the frosting is still fresh, push one Kit Kat vertically until you have circled the entire cake. Secure with a ribbon. I use the curling wrapping ribbon. Fill the well that has been made by the Kit Kat bars with the strawberries and blueberries - Enjoy!