Preheat a 10" oven-proof skillet in a 425ºF oven.
In a large bowl, whisk the eggs until frothy. Whisk in the milk, vanilla, sugar and salt, and then add the flour. Whisk again just until most of the lumps are gone.
Using oven mitts, remove the hot skillet from the oven. Add the butter and swirl to coat the bottom and sides of pan. Pour in the batter and (again, using oven mitts!) transfer to the oven. Bake until puffy and golden, 9-12 minutes. Serve with Rhubarb Curd or yogurt, blueberries and maple syrup.