Step 1

Preheat oven to 350°F and grease a 9x13-inch baking dish with nonstick spray. Spread potatoes out evenly in pan and set aside.

Step 2

In a large saucepan, combine milk, heavy cream, dry mustard, salt, garlic powder, parsley, and black pepper. Place over medium-low heat and add cheese, stirring frequently until cheese melts.

Step 3

Pour cheese mixture over potatoes and bake, uncovered, until edges have turned golden brown, about 60 minutes. Enjoy!