Prepare a large pot of salted water and bring to a rolling boil. Boil the rigatoni until it reaches al dente texture, making sure to reserve a half-cup of starchy pasta water before draining.

Warm the olive oil in a heavy skillet over medium-high heat. Season your steak cubes generously with salt and pepper, then sear them in batches until a golden crust forms and they reach your desired doneness.

Transfer the seared steak to a side plate to rest. In the same skillet, melt the butter while scraping up the flavorful browned bits from the bottom.

Stir in the minced garlic and sauté for about 30 seconds until the aroma fills your kitchen.

Pour the heavy cream into the skillet and simmer gently for 2 to 3 minutes until the liquid begins to thicken slightly.

Lower the heat and whisk in the freshly grated Parmesan cheese until the sauce is completely smooth and glossy.

Fold the cooked rigatoni into the cream sauce, adding a splash of the reserved pasta water if you prefer a thinner consistency.

Gently stir the rested steak and any accumulated juices back into the pan. Garnish with fresh parsley and serve immediately while steaming hot.