Preheat oven to 375°F. Grease a 9×13-inch baking dish with the oil.
Brown the sausage in a large skillet over medium heat, breaking it into small crumbles.
Melt the butter in the skillet with the sausage. Sprinkle in the flour and cook, stirring, 1–2 minutes.
Slowly whisk in the milk until smooth. Simmer, stirring often, until thick and bubbly, 4–6 minutes.
Season the gravy with salt, black pepper, garlic powder, onion powder, and red pepper flakes. Remove from heat.
Cut the biscuit dough into quarters or small bite-size pieces.
Fold the biscuit pieces and half of the cheddar into the hot sausage gravy.
Spread the mixture evenly in the prepared dish. Sprinkle with the remaining cheddar.
Bake until biscuits are cooked through and the top is golden, 22–28 minutes. If browning early, tent with foil.
Rest 5 minutes. Garnish with parsley and serve warm.