German Apple Pancake (Apfel Pfannekuchen)

6 cooking apples, cored, thinly sliced
1/3 stick butter
1/3 cup sugar
Freshly grated nutmeg
6 eggs
1/2 tsp. vanilla extract
1 cup flour
1 cup milk

In an 8-inch cast iron skillet, melt butter and saute sliced apples; add sugar, cinnamon and nutmeg (to taste) and cook slowly until sugar is melted and apples begin to soften. In the meantime, mix eggs, vanilla, flour and milk; pour liquid over apples. Bake for 20-30 minutes in pre-heated oven at 375°F until puffed and done in center.