Begin by bringing a large pot of salted water to a rolling boil. Add the pasta and cook until just al dente, about 8 minutes, stirring occasionally. Drain and set aside, reserving about ½ cup of pasta water.
While the pasta cooks, heat the olive oil in a deep skillet over medium heat until it shimmers and begins to smell fragrant. Add the sliced garlic and cook for about 1-2 minutes, stirring frequently, until it turns golden and releases a rich aroma.
Add the shrimp to the skillet in a single layer. Sauté for about 2-3 minutes per side, until they turn pink and are just cooked through. They should be tender and juicy, with a slight bounce when pressed.
Pour in the lemon juice and add a splash of the reserved pasta water to loosen the oil and create a light sauce. Toss the pasta into the skillet, mixing everything well so the noodles are coated with the fragrant oil and lemon.
Season with salt, pepper, and red pepper flakes if using. Toss again to combine, letting the flavors meld for about a minute. The dish should look glossy, with the ingredients beautifully coated and vibrant.
Remove from heat, sprinkle with lemon zest for a fresh aroma, and serve immediately. Enjoy this simple, elegant pasta while the shrimp are tender and the flavors are bright.