Heat oven to 450ºF. Place the butter in the bottom of the pan and place it in the oven until the butter melts and the pan is nice and hot. Then remove from the oven. Do not brown!
Next, in a large bowl, whisk together eggs, milk, flour, sugar, vanilla, salt, and lemon zest. Be sure the batter is completely smooth. You can also use a blender, hand mixer, or stand mixer, but a wire whisk works fine.
Slowly pour the batter into the pan on top of the melted butter and pop it back in the oven. Bake for 10-15 minutes until the pancake puffs up and turns golden brown. Be careful not to over brown (see note below).
Remove pancake from the oven, slice into 4ths, and top each slice with powdered sugar and a drizzle of lemon juice (to taste), or any other topping you've chosen, while still warm. Serves 2-4.
