Preheat your oven to 425°F (220°C).
Place your oven-safe skillet in the oven while it’s preheating.
In a mixing bowl, combine the all-purpose flour, granulated sugar, and sea salt. In another bowl, whisk together the milk, eggs, and vanilla extract until smooth. Gradually add the dry ingredients to the wet ingredients, whisking until fully combined.
Once the oven is preheated, carefully remove the skillet. Add 6 tablespoons of unsalted butter to the skillet and return it to the oven until the butter is melted and bubbly.
Pour in the batter over the melted butter.
Return the skillet to the oven and bake for about 20-25 minutes until golden brown.
Remove from the oven and sprinkle with extra granulated sugar. Serve immediately with your favorite toppings.
