Bring a large pot of salted water to a rolling boil and cook the pasta until just shy of al dente, about 1-2 minutes less than package instructions. Drain, reserving about 1 cup of pasta water, and set aside.
Pat the shrimp dry and season lightly with salt and a pinch of red pepper flakes if using. Heat 2 tablespoons of olive oil in a large deep skillet over medium-high heat until shimmering.
Place the shrimp in the hot oil in a single layer. Cook for about 2-3 minutes per side until they turn pink, opaque, and slightly golden. Remove the shrimp with a slotted spoon and set aside.
Lower the heat to medium, add the remaining 1 tablespoon of olive oil to the same skillet, and add the minced garlic. Sauté for about 30 seconds until fragrant and just beginning to turn golden, being careful not to burn.
Add torn basil leaves to the skillet and stir just for 10 seconds until aromatic. This releases their fragrance and brightens the oil.
Return the cooked shrimp to the skillet and toss gently to coat in the garlic and basil oil. Warm them through for about 1 minute.
Add the drained pasta to the skillet, tossing with tongs to evenly coat in the flavors. Gradually pour in some reserved pasta water, about 1/4 cup at a time, to loosen the sauce and help everything stick together.
Squeeze the fresh lemon juice over the pasta and toss again. Taste and adjust seasoning with salt and pepper as needed. Sprinkle additional basil leaves for a fresh visual and flavor finish.
Serve immediately, garnished with extra basil leaves and a drizzle of olive oil if desired. The pasta should be glossy, fragrant, and vibrant with herbs and seafood.
