German Pancakes, Puff Pancake, Old-World, Or Dutch Baby Pancake... Whatever you call them, they are delicious! Easy to make with minimal ingredients and big flavor.
Place the butter in the center of a 9x13 baking dish and place it in a cold oven. Turn the oven on to preheat to 425 °F.
While the oven is preheating, combine the milk, flour, eggs, sugar, vanilla, and cinnamon (if using) into a blender. Pulse 3 to 5 times or until mixed together fully.
Once the butter is melted in the baking dish, remove from the oven and pour the batter directly on top of the melted butter. Don't mix.
Bake for 20 to 25 minutes, or until the sides are puffed up and the center has set.