Bring a large pot of salted water to a boil and cook fettuccine until al dente.
Season steak strips with salt and black pepper.
Heat olive oil in a large skillet over medium-high heat. Sear steak strips until browned, approximately 2-3 minutes per side. Remove steak from skillet and set aside.
Reduce heat to medium and melt butter in the same skillet. Add minced garlic and sauté for 60 seconds until fragrant.
Whisk in heavy cream and bring to a simmer for 3-5 minutes until slightly reduced.
Add grated Parmesan cheese and red pepper flakes, stirring until the sauce is smooth and thickened.
Combine the cooked pasta and seared steak with the cream sauce, tossing to ensure even coating.
Garnish with chopped fresh parsley before serving.