In a large pot, boil salted water and cook the linguine or spaghetti according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of the pasta water.
In a large skillet over medium heat, melt the unsalted butter. Once melted, add the minced garlic and red pepper flakes. Sauté for 1-2 minutes until fragrant.
Add the shrimp to the skillet and season with salt and pepper. Cook for 2-3 minutes on one side, then flip and cook until the shrimp are pink and opaque (about 2 minutes more).
Add the lemon zest and juice to the skillet. Stir in the chopped parsley and cherry tomatoes (if using). If the sauce is too thick, gradually add the reserved pasta water until you reach your desired consistency.
Toss the cooked pasta into the skillet with the shrimp and sauce, ensuring it is evenly coated. Cook for an additional minute to allow the flavors to meld.
Plate immediately, garnishing with extra parsley and a sprinkle of lemon zest if desired.
Notes
Adjust the red pepper flakes to your spice preference.