Cook macaroni according to package until al dente; drain and set aside.
Brown hot dogs in a large skillet over medium 3-4 minutes until slightly caramelized; remove and set aside.
Melt butter in pasta pot over medium; whisk in flour and cook 1-2 minutes to form roux.
Gradually whisk in milk; keep whisking about 5 minutes until thickened.
Remove from heat; stir in cheddar and mozzarella until completely melted and smooth.
Add salt, pepper, and garlic powder; fold in macaroni and hot dogs.
Serve immediately, hot and creamy, or transfer to a baking dish and bake at 350°F for 15 minutes for a crispy top.