Step 1

Arrange a rack in the middle of the oven and heat the oven to 400ºF. Line a rimmed baking sheet (about 13x18 inches) with parchment paper.

Step 2

Melt 8 tablespoons unsalted butter in a small saucepan over medium heat or in a small microwave-safe bowl. Coat the parchment paper and sides of the baking sheet with about 1 tablespoon of the melted butter.

Step 3

Place 2 cups buttermilk, 2 large eggs, 1 teaspoon vanilla extract, and 4 tablespoons of the melted butter in a large bowl and whisk until combined. Add 2 cups all-purpose flour, 1/4 cup granulated sugar, 2 teaspoons baking powder, 1 teaspoon baking soda, and 1 teaspoon kosher salt. Fold with a spatula or wooden spoon until the dry ingredients are incorporated, some small lumps are okay. Fold in 1 1/2 cups chopped fruit, nuts, or chocolate chips, if desired.

Step 4

Pour the batter into the prepared baking sheet and smooth into an even layer. Bake until the pancake is lightly golden, cracked, and springs back when touched, 12 to 15 minutes.

Step 5

Remove the pancake from the oven and heat the broiler to high. Brush the remaining 3 tablespoons melted butter onto the pancake. Broil until golden brown, 2 to 4 minutes. Cut into 12 pieces and serve warm with powdered sugar and maple syrup.