Bring a large pot of salted water to a rolling boil, then add the pasta and cook until just shy of al dente, about 8 minutes. Drain and set aside, reserving a small cup of pasta water.
While the pasta cooks, peel and devein the shrimp if needed, then pat them dry with a paper towel. Slice the garlic thinly and set aside.
Heat 1 tablespoon of butter in a deep skillet over medium-low heat until melted and fragrant. Add the sliced garlic and cook slowly, stirring occasionally, until golden and aromatic, about 2-3 minutes. Keep the heat low to prevent burning.
Increase the heat to medium and add the shrimp to the skillet. Sauté until pink and opaque, about 2-3 minutes per side, making sure they stay juicy and tender.
Add the cooked pasta directly into the skillet with the shrimp. Toss gently to coat the noodles in the garlic butter sauce. If the mixture seems too thick, splash in a little of the reserved pasta water and stir until glossy and smooth.
Squeeze the lemon juice over the pasta and shrimp, then season with salt, pepper, and red pepper flakes if using. Toss everything together to combine thoroughly.
Remove the skillet from heat, sprinkle with chopped herbs if desired, and give one final toss. Serve immediately, enjoying the fragrant, glossy pasta topped with plump shrimp and fresh herbs.
