Prepare the Pasta:

Cook the macaroni in salted boiling water as per package instructions. (minus 2 minutes). Drain and set aside. You want the pasta to be firmer than soft as it still needs to bake.

In a large pot, melt 1 tablespoon of unsalted butter over medium heat. Add the cooked pasta and toss to coat. Set aside and allow to cool.

Make the Sauce:

In a separate saucepan, melt 4 tablespoons of unsalted butter over medium heat.

Add the flour and cook, stirring constantly, for about 1 minute until the mixture is golden and bubbly.

Gradually whisk in the warm milk, ensuring there are no lumps.

Continue to cook, stirring frequently, until the sauce thickens, about 5-7 minutes.

Remove from heat and stir in the shredded cheese, mozzarella, mustard, and salt until smooth and creamy.

Combine and Bake:

Preheat your oven to 350°F (175°C).

Pour the cheese sauce over the cooked pasta and mix until the pasta is evenly coated.

Transfer the pasta mixture to a greased casserole dish. 2.5L/2.5qt (10 cup) baking dish will work.

Add the Cheetos Topping:

Sprinkle the crushed Cheetos evenly over the top of the mac and cheese. It is easiest to crush the Cheetos in the bag with a baking pin or with your hands. You can also put the Cheetos into a blender and pulse for a few seconds.

Bake in the preheated oven for 20-25 minutes or until the top is golden and crispy.

Serve:

Allow the casserole to cool for a few minutes before serving. Enjoy this spicy, cheesy dish on its own or with a side of ketchup for an extra tangy kick.