Once the butter in the oven is melted, remove pan from the oven and spread the apples in a layer on the bottom of the pan. Place the pan back in the oven while you make the batter.

In a medium bowl, combine eggs, flour, milk, vanilla, and salt. Whisk until smooth and uniform

Take the pan out of the oven and pour the batter over the apples.

Bake for 18-20 minutes, until the center is set and the sides are really puffy and golden-brown.

Once you take the dish out of the oven, it will begin to deflate (that's okay!). Serve immediately with toppings of your choice (Powdered sugar or whipped cream is a fabulous way to finish this off, but it’s also sweet enough to stand on its own).