Best Scalloped Potatoes | Easy Scalloped Potato Recipe

Ingredients

• 6 potatoes (medium, peeled and thinly sliced)
• 4 tablespoons butter
• 3 tablespoons flour
• 1 teaspoon salt
• 1/4 teaspoon pepper
• 2 1/2 cups milk
• 1 onion (small, finely chopped)