Preheat oven to 400 degrees.
Combine 4 1/2 cups all purpose flour, 2 tablespoons baking powder, 1 1/2 teaspoons salt, and 2 tablespoons of sugar in a bowl until evenly mixed.
Cut in 1 cup of shortening until mixture resembles coarse crumbs.
Add 1 3/4 cups buttermilk and mix until soft and combined.
Turn dough out onto generously floured surface.
Roll out into a 1 1/4" slab.
Use a biscuit cutter or glass to cut out biscuits; roll up excess scraps and re-roll another slab to cut more biscuits until little to no dough remains.
Brush with melted butter.
Bake on a baking sheet for 17-22 minutes until golden brown.
Remove from oven, brush again with melted butter while still hot.