1. Preheat oven to 425 degrees F
2. Press potatoes in a 9" baking dish that has been sprayed with cooking spray. Drizzle butter or olive oil on top and sprinkle with seasoning salt. Bake for 25 minutes.
3. Combine ham, onion and cheese in a small bowl. In a separate bowl, whisk together eggs, milk, salt, pepper and a little seasoning salt. Spread meat mixture on top then pour egg mixture over all.
4. Reduce oven to 350 degrees F. Bake for 30 minutes.