Measure out 1/2 cup of each shredded cheese (colby jack, white cheddar, sharp cheddar) and set aside for the topping.
Bring a large pot of salted water to a boil. Cook the elbow macaroni according to the package directions until al dente. Drain the macaroni and transfer it to a 9x13 baking pan. Add the cubed butter and stir until completely melted and the macaroni is well coated.
In a large saucepan, combine the evaporated milk, heavy whipping cream, the remaining shredded cheeses, and the spices (paprika, onion powder, garlic powder, salt, and pepper). Whisk over medium-low heat, stirring constantly until the cheeses are fully melted and the sauce is smooth and creamy.
Pour the cheese sauce over the cooked macaroni in the baking pan. Mix well to ensure all the macaroni is evenly coated with the sauce.
Sprinkle the reserved 1/2 cup of each shredded cheese on top of the macaroni. Preheat the broiler on your oven. Place the pan under the broiler for 5-6 minutes, or until the cheese on top is melted and browned.
Notes
Try with mix-ins like crispy cooked bacon, steamed broccoli florets, or browned onions.