How to Make It
In a large frying pan, heat 1 tablespoon of the oil over moderate heat. Season the steak with 1/4 teaspoon each of the salt and pepper and add it to the pan. Brown on all sides, about 4 minutes, and remove. The meat should be medium rare.
Add the remaining 1 tablespoon oil to the hot pan, along with the mushrooms and 1/4 teaspoon of the salt. Cook for about 2 minutes. Remove the mushrooms from the pan and add to the steak.
Add the shallot, broth, and Worcestershire sauce to the hot pan. Cook, stirring, to dislodge any browned bits that cling to the bottom of the pan. Simmer until the liquid is reduced to about 1/3 cup, approximately 5 minutes.
Add the cheese and the cream to the pan along with the steak and mushrooms and any accumulated juices, the remaining 1 teaspoon salt and 1/2 teaspoon pepper, and the parsley. Simmer to heat through, about 1 minute.
Meanwhile, in a large pot of boiling, salted water, cook the rigatoni until just done, about 14 minutes. Drain the pasta and toss it with the sauce.