Bring a large pot of salted water to a rolling boil and cook the pasta until just al dente, about 8 minutes. Drain and set aside, reserving a splash of pasta water.
While the pasta cooks, peel and devein the shrimp if needed. Pat them dry and season lightly with salt and pepper.
Heat the olive oil in a large skillet over medium heat until shimmering. Add the minced garlic and cook for about 30 seconds, until fragrant and golden, making sure not to burn it.
Add the shrimp to the skillet and cook for 2-3 minutes per side, until they turn pink and are just cooked through. Remove the shrimp from the skillet and set aside.
In the same skillet, toss in the cooked pasta and stir to coat it with the garlic oil. If it looks dry, add a splash of the reserved pasta water to loosen everything up and create a glossy sauce.
Squeeze the fresh lemon juice over the pasta, then sprinkle in the red pepper flakes and chopped parsley. Toss everything gently to combine and evenly distribute the flavors.
Return the cooked shrimp to the skillet and toss again to combine. Taste and adjust seasoning with more salt, pepper, or lemon if needed.
Cook for another minute just to warm the shrimp through, then remove from heat. Serve immediately, garnished with extra parsley and lemon zest if desired.
