Easy Mashed Potato Casserole Recipe

Ingredients

• 2 tablespoons butter
• 9 large potatoes, peeled
• 1 (8 ounce) container sour cream
• 1 (6 ounce) package cream cheese
• 1 teaspoon onion salt
• 0.5 teaspoon garlic powder
• 1 dash ground black pepper
• 0.5 cup shredded Cheddar cheese
• 1 pinch dried parsley flakes, or to taste
• 1 pinch paprika, or to taste