In a large bowl, combine flour, sugar, salt, and baking powder.
Cut in butter using a pastry blender, two knives, or your fingers, until mixture resembles wet sand.
Stir in blueberries, making sure they get coated with flour mixture.
Stir in 1 cup buttermilk, taking care to incorporate the dry ingredients well while not crushing the blueberries. Add more buttermilk as needed to form into a cohesive dough.
Turn out dough onto a lightly floured surface and pat into a 1/2 inch thick rectangle. Fold once, pat again, and fold again. Repeat as needed for dough to look smooth but not be overworked.
Pat into a rectangle or circle and cut out biscuits. Reshape as needed to cut out remaining dough.
Place biscuits on a baking sheet, slightly separated, and freeze while preheating the oven to 425°F.
Once the oven is ready, bake for 20 minutes, or until golden brown.
Serve warm with butter or with sweet biscuit icing drizzled over the top.