Preheat the oven to 400°F, and grease an 11x7-inch or 9x9-inch pan with cooking spray.
Place the potatoes into a large pot of salted water and bring to a boil. Cook until the potatoes are fork tender but not so soft that they're mashable. Drain, and return to the pan (off the burner/remove from heat).
4 cups potatoes
While the potatoes boil, cook the sausage. Place a medium skillet over medium heat, and cook the sausage until browned and carmelized to your liking. Stir frequently to prevent burning. Transfer the sausage to the pan of drained potatoes.
14 ounces smoked sausage
In a medium pan over low heat, melt the Velveeta, butter, milk, salt, garlic powder, onion powder, and pepper. Stir often to keep the sauce from scorching. Once melted and creamy, pour the sauce over the potatoes and sausage and stir gently to coat.
16 ounces Velveeta, ½ cup unsalted butter, ½ cup milk, 1 teaspoon salt, ½ teaspoon garlic powder, ¼ teaspoon onion powder, ¼ teaspoon ground black pepper
Transfer to the prepared baking dish, and top with shredded cheese if using. Bake for 15-20 minutes or until the sauce bubbles around the edges.
½ cup sharp cheddar cheese
Serve warm! Scroll up and see the post for tips, substitutions, answers to frequently asked questions, and storage information.