Bring a large pot of salted water to a rolling boil. Add the pasta and cook until just al dente, about 8-10 minutes. Drain, reserving a quarter cup of pasta water, and set aside.
While the pasta cooks, heat a large skillet over medium-high heat and add 2 tablespoons of olive oil. Once shimmering, add the shrimp in a single layer and sear for 2-3 minutes on each side until they turn a bright pink and develop a slight char. Remove the shrimp from the skillet and set aside.
In the same skillet, lower the heat to medium and add the minced garlic along with red chili flakes. Cook, stirring constantly, until fragrant, about 30 seconds. Be careful not to burn the garlic.
Pour in the reserved pasta water and stir, scraping up any browned bits from the bottom of the skillet. Add the cooked pasta to the skillet and toss to coat the noodles evenly in the spicy garlic sauce.
Return the cooked shrimp to the skillet and toss everything together. Cook for another 1-2 minutes until heated through, allowing the flavors to meld. Season with salt to taste.
Finish by squeezing fresh lemon juice over the pasta and sprinkling chopped parsley. Toss gently to combine, then remove from heat.
Serve immediately while hot, garnished with extra parsley if desired, and enjoy the bold, spicy, garlicky flavors in every bite.
