1. Bring a large pot of salted water to a boil. Cook spaghetti until al dente. Reserve ½ cup of pasta water, then drain.

2. Slice the beef into thin strips and season with salt, pepper, and Cajun seasoning.

3. Heat olive oil in a skillet over medium-high heat. Sear beef strips in batches for 2–3 minutes per side until browned. Set aside.

4. In the same skillet, melt butter over medium heat. Add minced garlic and sauté for about 1 minute until fragrant.

5. Stir in 1 tablespoon Cajun seasoning, then pour in the heavy cream. Simmer gently.

6. Add grated Parmesan and stir until the sauce thickens slightly.

7. Toss the cooked spaghetti into the sauce and combine well. Add pasta water as needed to loosen the sauce.

8. Plate the pasta and top with seared beef strips.

9. Garnish with fresh parsley if desired and serve hot.