01 - Bring a large pot of salted water to a boil and cook the pasta until al dente according to package directions. Reserve 1/2 cup pasta water then drain the pasta.
02 - Pat the shrimp dry and season with salt and freshly ground black pepper.
03 - Heat unsalted butter and olive oil in a large skillet over medium heat. Add minced garlic and crushed red pepper flakes if using; sauté for about 1 minute until fragrant but not browned.
04 - Add shrimp in a single layer and cook 1 to 2 minutes per side, until shrimp are pink and cooked through. Remove shrimp from skillet.
05 - Add lemon zest, lemon juice, and white wine or chicken broth to the skillet. Simmer for 2 minutes, scraping up browned bits from the pan.
06 - Return the drained pasta to the skillet and toss to coat with the sauce. If the sauce is too thick, add reserved pasta water a little at a time to reach desired consistency.
07 - Return cooked shrimp and chopped parsley to the skillet and toss gently to combine. Adjust seasoning as needed.
08 - Serve immediately, garnished with freshly grated Parmesan cheese and lemon wedges if desired.