Peel and cube the potatoes, then rinse them under cold water to remove excess starch.

Boil the cubed potatoes in salted water until fork-tender, about 10-15 minutes. Drain well afterward.

In a large mixing bowl, combine the sour cream, melted butter, garlic powder, onion powder, salt, and pepper. Stir until smooth and creamy.

Gently fold in the drained potatoes and half of the shredded cheddar cheese until well-coated.

Transfer the mixture to a greased baking dish. Top with remaining cheese and optional breadcrumbs. Bake at 350°F (175°C) for 25-30 minutes.