Fill a large pot with salted water and bring it to a boil over high heat. Once boiling, add 8 ounces of pasta, stirring occasionally to prevent sticking. Cook according to the package instructions until al dente, usually around 8-10 minutes. Once done, drain the pasta, reserving a bit of the cooking water, and set it aside while you prepare the sauce.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add 1 small diced onion and sauté for about 5-7 minutes until it's softened and translucent. Stir occasionally to ensure even cooking.

Next, stir in 4 minced cloves of garlic and 1 teaspoon of red pepper flakes into the pan. Cook for about 1 minute, stirring continuously, until the garlic is fragrant and lightly golden.

Pour in 1 can (28 ounces) of diced or crushed canned tomatoes into the skillet. Stir well to combine all ingredients. Allow the sauce to simmer for about 10 minutes, breaking up the tomatoes with a spoon.

Carefully add 1 pound of peeled and deveined shrimp to the simmering tomato sauce. Cook for 2-3 minutes per side, using a spatula to flip, until the shrimp turn pink and opaque.

Once the shrimp are fully cooked, season the sauce with salt and pepper to taste. Gently incorporate the reserved pasta into the skillet, tossing to coat it evenly in the sauce.

Serve your shrimp fra diavolo immediately, garnished with fresh basil or parsley if desired.