Preheat your grill/smoker to 350 degrees F. Grease an 8x8 pan with nonstick spray. (I used a tinfoil disposable pan.)
In a a large pot (3 quart should do), boil the pasta according to package instructions. Don't add any salt or oil to the water as there's enough in the recipe already. It should take about 6-8 minutes or so. Drain and return to the pot.
Tip: If your cheese sauce is not close to being ready, add some oil (1-2 teaspoons) to help prevent your pasta from sticking.
Cook bacon until done. I personally prefer mine a bit crispy, but doesn't matter too much since it's going to become softened when cooked with the mac and cheese. Once done and cooled enough to touch, crumble it.
In another medium sized pot, melt 1/4 cup butter. Once it is hot, whisk in the flour. Cook 1 minute whisking, until it is bubbly.
Slowly stir in the cream and milk, add the salt and pepper, and continue stirring until it is thick.
Remove from heat and add the chopped green chile and crumbled bacon. Gradually stir in the shredded mozzarella and cheddar. If it is not melting, put it back on the burner over very low heat, stirring until the cheese is incorporated.
Stir the cheese sauce into the cooked macaroni. Yes, it's pretty thick!
Pour half of the mac and cheese into the prepared pan.
Layer the cheddar and jack cheese slices on top of the macaroni.
Pour the other half of the mac and cheese on top and spread evenly.
(Optional) In a small bowl, melt 1/4 cup butter and stir in the bread crumbs or crushed ritz crackers, then spread the mixture on top of the mac and cheese.
Place on your grill/smoker and bake for 20-25 minutes. The top should be turning golden brown and the mac and cheese should be bubbly.
Vegetarian Tip: You can keep this vegetarian by simply omitting the bacon.
I used half sharp cheddar and half Monterey Jack cheese slices, but feel free to use another cheese of your choice such as Gouda.
You can also make this ahead of time. Simply assemble the mac and cheese without the crumb topping ahead of time (1-2 days) and store covered in the fridge. Add the crumb topping (if using) and then bake when you are ready to serve. Just remember that you'll have to bake it a little longer if you put it on the grill/smoker cold. (Probably about 30-40 minutes).