01 -
Pat ribeye cubes thoroughly dry with paper towels. Place in a mixing bowl, drizzle with vegetable oil, sprinkle Cajun seasoning, and massage until evenly coated. Set aside.
02 -
Heat a large skillet or cast iron pan over high heat until nearly smoking. Add steak cubes in a single layer and cook undisturbed for 2 to 3 minutes until a deep brown crust develops. Flip quickly, sear other side, then transfer steak to a plate to prevent overcooking.
03 -
Reduce heat to medium. Add 2 tablespoons unsalted butter to pan. When melted, stir in minced garlic and cook about 1 minute, scraping browned bits from pan for flavor.
04 -
Return seared steak and accumulated juices to skillet. Toss in garlic butter until evenly coated. Top with chopped parsley, turn off heat, cover, and keep warm.
05 -
In a separate saucepan, melt 4 tablespoons butter over medium-low heat. Whisk in flour gradually and cook, whisking continuously for 2 minutes until pale and nutty but not browned.
06 -
Stir in half the garlic powder and smoked paprika. Gradually whisk in whole milk until smooth, then add heavy cream while whisking.
07 -
Add half of each mozzarella, Colby Jack, and sharp cheddar cheese by small handfuls, stirring between additions until fully melted. Season sauce with salt and black pepper to preferred taste.
08 -
Prepare elbow macaroni according to package instructions until just al dente. Drain thoroughly but do not rinse.
09 -
Transfer drained macaroni into cheese sauce and stir thoroughly to evenly coat every piece.
10 -
Preheat oven to 350 degrees Fahrenheit. Spoon half the macaroni and cheese mixture into a greased baking dish. Sprinkle with remaining shredded cheeses, then top with rest of macaroni and cheese. Finish with additional mozzarella and cheddar for a crisp topping.
11 -
Bake for 20 minutes until bubbling. Switch oven to broil setting and cook 3 to 4 minutes more, monitoring closely, until cheese is golden brown and crisp.
12 -
Serve immediately, topping with steak bites and extra parsley if desired.