Set your oven to preheat at 375 degrees Fahrenheit.
Cook the macaroni noodles following the package instructions until just firm to the bite, then drain and keep aside.
In a large mixing bowl, combine the drained pasta with the melted butter, stirring until well coated.
Pour in the heavy cream, half and half, and sour cream, then season with seasoning salt, garlic powder, onion powder, and black pepper, stirring everything together thoroughly.
Mix in the beaten eggs along with 16 ounces of the shredded Monterey Jack cheese, blending well.
Add the shredded sharp cheddar cheese and thoroughly fold it into the pasta mixture.
Prepare a baking dish by greasing it with butter or by spraying it with non-stick spray, then transfer the macaroni mixture into the dish evenly.
Top the macaroni with the remaining 8 ounces of shredded Monterey Jack cheese, spreading it across the surface.
Place in the oven and bake for 35 to 40 minutes until the mac and cheese is bubbling and the top has turned golden brown.
Take the dish out of the oven and let it rest for 5 to 10 minutes before serving to allow it to set and develop flavor.