Instructions

• Bring a medium saucepan of water to a rolling boil and add ½ teaspoon salt. Add 8 oz (225 g) pasta and cook according to the package instructions until al dente. Before draining, scoop out and reserve 1 cup of the pasta cooking water, then drain the pasta.
• While the pasta cooks, heat a large skillet over medium heat and add 1 tablespoon olive oil and 1 tablespoon butter.
• Add 7 oz (200 g) sliced cremini mushrooms to the skillet, season with ¼ teaspoon ground black pepper, and cook, stirring occasionally, until the mushrooms are tender and lightly browned, about 3–4 minutes.
• Add 1 clove minced garlic to the mushrooms and cook, stirring, until fragrant, about 30 seconds.
• Pour in ½ cup heavy cream, add ½ cup grated Parmesan and 1 teaspoon Cajun seasoning (or smoked paprika), and stir constantly until the Parmesan melts and the sauce is smooth.
• Add reserved pasta water a little at a time (up to the full 1 cup) to loosen the sauce to your desired consistency, then allow the sauce to simmer gently for about 1 minute.
• Taste the sauce and adjust seasoning with salt or pepper if needed.
• Add the drained pasta to the skillet and toss until the pasta is well coated in the sauce.
• Add 1 pound (450 g) cooked prime rib (sliced into bite-size pieces) to the pasta and stir just until the meat is warmed through, about 1–2 minutes.
• Remove from heat, sprinkle with 2 tablespoons chopped fresh parsley, and serve immediately.