Bring a large pot of salted water to a rolling boil. Add the pasta and cook until just shy of al dente, about 1 minute less than package instructions. Drain, reserving a cup of starchy pasta water.
While the pasta cooks, heat the olive oil in a large deep skillet over medium heat. Once shimmering, add the sliced garlic and cook until fragrant, about 30 seconds, stirring gently to prevent burning.
Add the shrimp to the skillet and cook for 2-3 minutes per side, until they turn pink, firm, and opaque. Use a slotted spoon if needed to handle the shrimp without breaking them.
Lower the heat slightly and add the red pepper flakes, stirring briefly to release their aroma. Squeeze the lemon juice over the shrimp and add the lemon zest for a bright, fresh flavor.
Transfer the drained pasta directly into the skillet with the shrimp, tossing gently to combine. Pour in a splash of the reserved pasta water to loosen the sauce and help it coat the noodles evenly.
Season with salt and freshly ground black pepper to taste. Continue tossing until everything is well coated and glossy, about 1-2 minutes, allowing the flavors to meld.
Remove the skillet from heat. Finish with a drizzle of good olive oil and sprinkle with chopped parsley if desired. Serve immediately with lemon wedges on the side for an added burst of freshness.
