Cook the Memphis Strips in the oven or air fryer as per packet instructions.
Cook pasta in rapidly boiling water until just cooked, drain and set aside.
To make your cheese sauce, melt the butter in a saucepan over medium-low heat. Add the flour and onion soup mix and continue to cook for a few minutes. Slowly add the milk, whisking continuously until you have a thick, creamy sauce. Stir in most of the cheese, leaving some for your topping.
Add the pasta to your cheese sauce and toss to coat. Place in an oven-proof dish and top with the Memphis Strips. Sprinkle with the remaining cheese and place under the grill for about 10 minutes until bubbling and golden.