Easy Mashed Potato Casserole

Ingredients (10)

• + 2 tablespoons butter add to pantry
• ✓ 9 large potatoes, peeled
• + 1 (8 ounce) container sour cream add to pantry
• + 1 (6 ounce) package cream cheese add to pantry
• + 1 teaspoon onion salt add to pantry
• + ½ teaspoon garlic powder add to pantry
• + 1 dash ground black pepper add to pantry
• + ½ cup shredded Cheddar cheese add to pantry
• + 1 pinch dried parsley flakes, or to taste add to pantry
• + 1 pinch paprika, or to taste add to pantry