Begin by marinating the flank steak in a mixture of Cajun seasoning, olive oil, and a splash of citrus juice in a resealable bag or bowl. Ensure the steak is evenly coated, then let it marinate for at least 30 minutes at room temperature.

While the steak marinates, bring a large pot of salted water to a rolling boil. Cook the rigatoni pasta according to package instructions until al dente, typically around 10–12 minutes. Once cooked, drain the pasta thoroughly, reserving a cup of pasta water if needed later for sauce consistency, and set aside.

Heat a skillet over high heat and add a drizzle of olive oil. Once hot, carefully place the marinated steak in the skillet, searing it for 3-4 minutes on each side until it reaches a nice golden crust and is medium-rare. Keep an eye on it to avoid overcooking.

After searing, remove the steak from the skillet and transfer it to a cutting board. Let it rest for 5 minutes before slicing it into bite-sized pieces.

In the same skillet, lower the heat slightly, and add the low-sodium beef broth, heavy cream, and grated Parmesan cheese. Stir continuously until the cheese melts and the sauce reaches a creamy consistency—about 3–5 minutes.

Add the cooked rigatoni pasta into the skillet with the creamy sauce, mixing thoroughly to coat the pasta evenly. If the sauce seems too thick, gradually add a bit of reserved pasta water to reach your desired consistency. Season with salt and pepper.

To serve, plate a generous portion of cheesy rigatoni and top it with the succulent Cajun steak tips. Optionally garnish with additional grated Parmesan.