Scalloped Potatoes Recipe

Scalloped Potatoes Recipe
Ingredients:
4 cups thinly sliced potatoes
3 tbsp butter
1 1⁄2 cups milk
3 tbsp all-purpose flour
1 cup grated sharp cheddar cheese
1⁄2 cup grated cheese (cheddar or Gruyere) for topping
Salt to taste
Optional: 1/2 cup sliced green onions, pinch of cayenne pepper
Instructions:
Preheat your oven to 375°F (190°C) and grease a baking dish.