Bring a large pot of salted water to a rolling boil. Add the spaghetti and cook until just al dente, about 8 minutes. Drain, reserving a cup of pasta water, and set aside.
While the pasta cooks, peel and devein the shrimp if needed, then pat them dry with a paper towel. This helps prevent splattering and ensures even cooking.
Heat a large skillet over medium-high heat. Add the olive oil and let it shimmer. Toss in the crushed garlic and sauté for about 30 seconds until fragrant and slightly golden.
Add the shrimp in a single layer. Cook undisturbed for about 2 minutes, watching for them to turn pink and start to firm up. Flip and cook the other side for another 1-2 minutes until fully opaque and glossy.
Pour in the white wine and let it simmer for 1 minute, allowing the alcohol to cook off and the liquid to reduce slightly, filling the pan with a fragrant aroma.
Transfer the drained pasta into the skillet with the shrimp. Toss gently using tongs, coating the noodles in the garlic, oil, and wine mixture. Add a splash of reserved pasta water if the sauce seems too thick.
Squeeze the fresh lemon juice over the pasta and shrimp. Toss again to combine, tasting for seasoning and adding salt or red pepper flakes as desired.
Cook for another minute until everything is hot and glossy. The shrimp should be tender, the pasta coated in a bright, flavorful sauce, and the aroma inviting.
Remove from heat and transfer to plates. Garnish with chopped parsley if using, and serve immediately to enjoy the tender shrimp and flavorful pasta at their best.
