Step 1: Preheat your oven to 425°F (220°C). Place a 10-inch cast iron skillet (or an oven-safe heavy-bottomed pan) into the oven while it preheats. This ensures the pan is very hot, which is crucial for the dramatic rise.
Step 2: In a blender, combine the room temperature milk, eggs, all-purpose flour, granulated sugar, vanilla extract, and a pinch of salt. Blend on high until the batter is completely smooth and airy, about 30-60 seconds. Scrape down the sides if necessary. Avoid overmixing.
Step 3: Carefully remove the hot skillet from the oven using oven mitts. Add the unsalted butter to the hot skillet. Swirl the butter around until it is completely melted and coats the bottom and sides of the pan. The butter should sizzle.
Step 4: Immediately and carefully pour the smooth batter into the hot, buttered skillet.
Step 5: Return the skillet to the preheated oven. Bake for 18-22 minutes, or until the dutch baby is dramatically puffed, deeply golden brown around the edges, and slightly less puffed in the center. Do not open the oven door during the first 15 minutes of baking.
Step 6: Once baked, carefully remove the dutch baby from the oven. It will begin to deflate almost immediately, which is perfectly normal and part of its charm.
Step 7: Transfer the dutch baby to a large serving platter or serve directly from the skillet. Dust generously with powdered sugar, add fresh berries, a squeeze of lemon juice, or any other desired toppings. Serve immediately and enjoy your spectacular dutch baby recipe!