Saute the onion and garlic in the olive oil in a small saucepan until the onion is tender but not brown. Combine the flour, salt and pepper in a bowl and mix well. Stir in the cheese, ham and mushrooms.
Whisk the milk and eggs in a bowl until well blended. Stir in the onion mixture. Add the milk mixture to the cheese mixture and mix well. Spoon into a greased 9-inch pie plate. Bake at 425 degrees for 30 minutes. Serve with fresh fruit and muffins.