Preheat oven to 425°F.
In a large bowl, whisk together flour, baking powder, sugar, and salt.
Cut in cold butter until mixture resembles coarse crumbs.
Stir in buttermilk just until dough comes together.
Turn dough onto a floured surface, gently fold a few times, and pat to 1-inch thickness.
Cut biscuits and place on a baking sheet.
Bake for 12–15 minutes or until golden brown.
Make the Sausage Gravy
In a skillet over medium heat, cook sausage until browned. Do not drain.
Sprinkle flour over the sausage and stir to coat. Cook for 1–2 minutes.
Slowly pour in milk while stirring continuously.
Bring to a simmer and cook until thickened.
Season with salt, black pepper, and optional heat to taste.