Preheat oven to 450°F. Place 1 tbsp unsalted butter in your 9 inch oven safe skillet and heat it in the oven for 5 minutes.
Add eggs, milk, flour, salt and 2 tbsp melted butter in a blender. Mix on high speed for 1 minute or until the batter is smooth.
Carefully remove the hot skillet from the oven and pour the batter into the skillet. Return the pan in the oven and bake for 20-25 minutes or until the pancake is puffed and brown around the edges. Don't open the oven door during the first 15 minutes of baking or you might deflate the pancake.
You can top your dutch baby with cooked eggs and bacon, cherry tomatoes and grated Parmesan cheese.