In mixer or blender, beat flour, milk, eggs, vanilla, salt, and nutmeg; set aside.
Heat oven to 475°F.
Heat cast iron skillet for 5 minutes, add 2 tablespoons butter; melt. Add sliced apples and fry 2 to 3 minutes. Pour mixture over apples.
Bake at 475° for 15 minutes. Reduce heat to 425° for 8 to 10 minutes.
Sprinkle with powdered sugar. Cut in wedges. Serve with syrup or jam and bacon.