Cook pasta to al dente, according to the package instructions. Drain and set aside.
Cook the bacon, then chop or crumble into bite-sized pieces and set aside.
Preheat your smoker on the smoke setting.
Add butter to a large pot over medium heat. Allow it to melt, but not sizzle. Add the flour and whisk together. Cook for 2 minutes.
Add the milk, evaporated milk, dry mustard powder, salt, and black pepper and whisk together. Stir while the mixture starts to thicken, 1-2 minutes.
Mix the three grated cheeses together in a bowl. Add 3/4 of the cheese mixture to the pot, stirring constantly until melted. Reserve the rest of the cheese (about 1 cup).
Once the cheese is melted and fully combined, add the pasta and stir well to incorporate.
Pour half the macaroni mixture into a smoker safe baking dish or disposable tin baking dish. Layer the remaining cheese evenly over the top then add the rest of the macaroni.
When the smoker is ready, place the mac and cheese on the grill. Smoke for 1 hour on the smoke setting.
Remove from the smoker and top with bacon. Serve immediately.