Place a 12-inch oven-safe skillet on a baking sheet and add 6 tablespoons salted butter to the skillet Transfer to the oven and heat to 400°F (200°C) while preparing the batter.
Place 6 large eggs, 1 1/2 cup milk, 1 1/2 cup all-purpose flour, 1/4 cup granulated sugar, 1 teaspoon vanilla extract, 1/2 teaspoon salt into a blender and beat on low to medium speed until frothy, which will take about 2 minutes. If the flour sticks to the side of the blender, be sure to scrape it down.
Once the butter in the skillet is melted and slightly browned, carefully swirl the skillet to coat the bottom and sides. Pour the batter into the hot skillet.
Bake for 18-20 minutes, until puffed and golden brown.
Remove from oven and serve immediately -- these taste great topped with powdered sugar or maple syrup.
Notes
Make sure the oven rack is on the lower half, but not the bottom rack setting. These will puff up quite a few inches and you don't want them too close to the heating elements.