To make this Creamy Mashed Potato Casserole gluten-free. Ensure that your mashed potatoes and chicken tenders. Are gluten-free by checking the labels. Or making them from scratch. Use a gluten-free brown gravy mix. Or make your own gravy. Using gluten-free flour. Or cornstarch as a thickener. With these simple adjustments. You can enjoy all the comforting flavors of this dish. Without worrying about gluten. It’s a perfect option. For those who need to avoid gluten. But still want to enjoy a hearty, home-cooked meal.