Preheat oven to 450 degrees.
Add flour, baking powder, and salt to a glass mixing bowl and stir together.
Pour in the melted butter and milk. Mix until incorporated well and a sticky dough forms.
Using a large spoon, scoop out the biscuit dough and drop in to cast iron skillet. You should get roughly 12 biscuits from this recipe.
Bake 12-15 minutes, or until biscuits are slightly golden brown on top. Brush top of biscuits with additional melted butter halfway through cook time if desired.