Cook the pasta in salted boiling water until al dente. Reserve 1/4 cup pasta water, then drain and set aside.
Heat olive oil and 1 tablespoon butter in a skillet over medium heat. Season shrimp with salt and pepper. Cook shrimp for 1-2 minutes per side until pink and opaque. Remove and set aside.
Add remaining butter to the skillet. Stir in garlic and red pepper flakes (if using) and cook for 30 seconds.
Pour in white wine (or chicken broth) and simmer for 1-2 minutes to reduce slightly.
Add pasta to the skillet, tossing to coat. Add reserved pasta water if needed to thin the sauce.
Return shrimp to the skillet, squeeze in lemon juice, and toss everything together.
Plate pasta and shrimp, garnish with parsley and Parmesan cheese, and serve immediately.