Fill a large pot with salted water and bring it to a boil. Add the rigatoni and cook according to package instructions until al dente, usually about 10-12 minutes. Reserve 1 cup of pasta water before draining.
While the pasta cooks, heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Season the steak strips generously with salt and pepper. Add them to the skillet and cook for about 2-3 minutes per side until browned but still tender. Remove the steak from the pan and set aside.
In the same skillet, add the remaining tablespoon of olive oil. Toss in the chopped onion, bell pepper, and garlic. Sauté until softened and fragrant, around 5 minutes.
Add the fire-roasted tomatoes, dried oregano, and red pepper flakes to the skillet. Stir well and let the sauce simmer for about 7-8 minutes, allowing the flavors to meld and the sauce to thicken slightly.
Return the cooked steak strips to the skillet. Toss in the drained rigatoni and mix everything together. If the sauce feels too thick, gradually add some reserved pasta water until you reach your desired consistency.
Taste and adjust the seasoning with salt and pepper. Serve the rigatoni garnished with fresh basil leaves and a sprinkle of grated Parmesan cheese if using. Enjoy immediately!