Preheat the oven to 350 degrees F.

Coat the bundt pan and the ramekin with nonstick spray.

In a mixing bowl, beat the cake mix, beets, egg whites, applesauce, milk, and vanilla until smooth. Spoon enough batter into the ramekin to fill by 2/3, then scrape the rest into the bundt pan. Bake until a toothpick inserted into the center comes out clean, about 15 minutes for the small cake and 30 minutes for the large one. Place on a rack to cool for 15 minutes. Turn the cakes out of the pans and let cool completely.

To assemble, cut the large cake in 1/2 crosswise and place the pieces end-to-end on the platter so they form an "S" shape. Use toothpicks to attach the small cake to 1 end to make the head. Use toothpicks to attach marshmallow "eyes" with raisin "pupils." Put the confectioners' sugar in a sieve or sifter and dust it generously over the cake.