In a medium bowl, mix the cream of mushroom soup, milk, garlic powder, onion powder, salt, and pepper. Stir until smooth and well combined.
Assemble the Casserole:
Pour the sauce mixture evenly over the layered potatoes, ham, and onions in the crockpot. Ensure everything is coated with the sauce.
Cook:
Cover the crockpot and cook on Low for 6-7 hours or on High for 3-4 hours, until the potatoes are tender.