Bring a large pot of water to a boil. Add salt and macaroni, and cook until al dente. Drain and return to the pot. Set aside.
Meanwhile, cook the bacon until crispy. Crumble into a small bowl and set aside.
In a large bowl, mix together the evaporated milk, milk, eggs and garlic powder until fully combined. In a separate bowl, mix together the cheeses.
Preheat the oven to 375°F. Lightly spray a 9×13 inch baking pan.
Layer ½ of the macaroni, then ½ of the cheese. Sprinkle with half of the crumbled bacon. Repeat with the remaining macaroni and cheese mixture. Pour the milk mixture over top. Sprinkle the remaining bacon evenly on top.