Melt butter in a saucepan over medium heat. Stir in flour and cook for 1-2 minutes until lightly golden.

Whisk in milk gradually along with garlic powder, onion powder (if using), salt, and pepper. Continue cooking for about 3-5 minutes, or until the mixture is thick and bubbly.

Spray your crock pot with non-stick cooking spray. Layer half of the sliced potatoes, then half of the diced ham, and sprinkle with ¾ cup of shredded cheese.

Repeat with the remaining potatoes, ham, and cheese.

Pour the cheese sauce evenly over all the layers. Cover and cook on low for 6-7 hours or on high for 3-4 hours, until the potatoes are tender and creamy.

Sprinkle with fresh parsley before serving.