Boil the linguine in salted water until al dente. Reserve 1/2 cup of pasta water before draining.
Heat the olive oil in a skillet over medium-high heat. Season the beef with salt and pepper, sear quickly for 3 to 4 minutes, then remove to a plate.
Melt the butter in the same skillet over medium-low heat. Add the minced garlic and cook for 1 minute until fragrant.
Pour in the heavy cream and simmer gently for 3 to 4 minutes to slightly thicken the base.
Stir the grated Parmesan into the cream until smooth, splashing in reserved pasta water to thin the sauce if necessary.
Toss the drained pasta and rested beef back into the sauce until heavily coated. Garnish with parsley and serve immediately.