01 - Bring a large pot of salted water to a boil. Cook spaghetti until al dente according to package instructions. Reserve 1/2 cup pasta cooking water, then drain.
02 - Pat shrimp dry and season with salt and black pepper.
03 - In a large skillet over medium heat, melt butter with olive oil. Add minced garlic and sliced chilies; sauté for 1–2 minutes until aromatic but not browned.
04 - Add shrimp in a single layer and cook 1–2 minutes per side until pink and opaque.
05 - Incorporate lemon zest and juice, stirring to evenly coat the shrimp.
06 - Add drained pasta directly to skillet. Toss thoroughly with shrimp and garlic-chili butter. Gradually add reserved pasta water if needed to loosen sauce.
07 - Stir in chopped parsley. Adjust seasoning with salt, pepper, or lemon juice as desired.
08 - Serve immediately, garnished with additional parsley, grated Parmesan, and lemon wedges if preferred.