Place the top oven rack just above the center position and pre-heat the oven to 425°F.

Combine the flour, eggs, milk, cinnamon, vanilla, sugar, and salt in a medium bowl and stir until just combined. Pour the batter into a blender and blend until aerated and no clumps remain approximately 1 minute.

Use the butter to thoroughly grease the exposed surface of the skillet, as shown, and then place in the hot oven just until melted. Remove from the oven and carefully swirl to ensure the butter is evenly distributed across the bottom of the skillet.

Pour the blended batter into the center of the hot skillet and place in the hot oven. Cook until the edges are puffed up and golden brown, approximately 20 minutes. Turn off the oven and allow the skillet to remain in the oven for 5 additional minutes.

Remove from oven and cool for a couple of minutes before slicing. Serve immediately topped with fresh fruit, powdered sugar, and/or maple syrup, if desired. Enjoy!