In a large mixing bowl, mix together eggs, butter, milk, water until smooth.
Add cake mix and mix until just combined.
Divide batter into 6 separate bowls.
Add a different color in each bowl and mix each batter until color is evenly distributed.
Drop spoonfuls of colored batter randomly in two round cake pans (Dimensions: 8x2). Pans should be lined with parchment paper and the sides should be greased.
Use a toothpick to swirl the colored batter.
Bake at 350 degrees F for 30-40 minutes or until an inserted toothpick in the center comes out clean.
Let the cakes cool completely.
While they are cooling, prepare whipped cream.
Trim off the cake domes (if any) and sides of the cake with a serrated knife.
Place one cake on a cake dish.
Use a spatula to spread whipped cream on top.
Then, place the other cake on top and press gently to secure it into place.
Use a spatula to spread whipped cream on top.
Toss m&m candies and sprinkles on top and enjoy.