Preheat oven to 425°F. Brush the inside of a 9 inch by 13 inch pan, or small sheet pan, with 1 tablespoon of melted butter, or spray with nonstick spray.
Place buttermilk, eggs, vanilla, and sugars in a large bowl and whisk until completely combined.
Sprinkle all-purpose flour, baking powder, baking soda, and kosher salt over the surface of the wet ingredients and begin folding together.
When halfway mixed, drizzle in cooled melted butter and finish combining just until the last of the dry ingredients are incorporated. Let rest for 10 minutes, if you can.
Spread pancake batter into prepared sheet pan, using a spatula to smooth the surface.
Slice your strawberries and blot them dry.
Place strawberries over the surface of your pancake batter, making it as pretty as you like. Bake at 425°F for 15 to 18 minutes until a skewer or toothpick inserted into the middle comes out clean and the pancake springs back to the touch.
Let cool for a few minutes before showering with powdered sugar. Slice and serve with maple syrup and more fruit.