1/4 cup dried potato flakes
1 cup ready-to-stick cooking marbles
1/4 cup butter
1/4 cup heavy cream
1 teaspoon vanilla extract
Preheat oven to 375 degrees F (190 degrees C).
Fill a 12-cup baking pan with enough water to cover potato flakes. Sprinkle baking marbles evenly over the potato skins. Bake in preheated oven for 10 minutes. Discard marbles.
In a medium bowl, cream together the butter and cream of potato. Blend in the vanilla, and pour into baked potato skins.
Bake for an additional 10 to 15 minutes, until set. Cool completely before cutting into wedges.