Bring a large pot of salted water to a boil. Cook pasta shells according to package directions until al dente. Drain, toss with a teaspoon of olive oil to prevent sticking, and set aside.

Pat the steak dry with paper towels. Season generously on both sides with paprika, salt, and pepper.

Heat 1 tablespoon olive oil in a large skillet over medium-high heat until shimmering. Add the steak and sear 3–4 minutes per side for medium-rare. Transfer steak to a cutting board and let rest for 5–10 minutes.

Reduce heat to medium. Add diced onion to the same skillet and sauté for 3–4 minutes, scraping up brown bits. Add minced garlic and cook for 30–45 seconds until fragrant.

Pour in the beef broth and bring to a simmer. Let the broth reduce by about half.

Stir in the heavy cream and heat gently until the sauce is warm and slightly thickened, about 2–3 minutes. Taste and adjust seasoning.

Slice or chop the rested steak into bite-sized pieces and return to the skillet to warm through.

Add the cooked shells to the skillet and toss gently until coated in sauce. If sauce seems too thick, loosen with a splash of pasta water or extra broth.

Serve immediately, garnished with chopped fresh parsley.