Preheat the oven to 225 C (425 F)
Combine the eggs, sugar, milk, flour, vanilla extract, and nutmeg and blend until smooth. You can also just whisk thoroughly by hand.
In a heavy 10 inch skillet or baking pan, put the butter. Place it in the oven until the butter melts. watching carefully so it doesn’t burn. One butter is melted, remove pan from oven and pour in all the batter. Layer the apple slices evenly on top of the batter, leaving the edges of the pan empty, much like a pizza crust.
Return the pan to the oven, and bake for 20 minutes until puffed and golden. Reduce oven temperature to 150 C (300 F) and bake for 5 minutes longer.
Drizzle with salted caramel sauce, top with your choice of ice cream, whipped cream, icing sugar and pecans/walnuts if desired and serve immediately.