Fill a large pot with water, add a generous pinch of salt, and bring it to a rolling boil. Cook spaghetti according to package instructions until al dente, about 8-10 minutes. Reserve 1 cup of pasta water before draining.

In a large skillet, heat olive oil over medium heat. Add shrimp, seasoning with salt and pepper. Cook for 2 minutes per side until they turn pink and opaque, then set them aside.

In the same skillet, add more olive oil if needed, toss minced garlic and red pepper flakes. Sauté for about 30 seconds until fragrant.

Pour in the crushed tomatoes, season with salt and pepper, and let the sauce simmer gently for 8-10 minutes until it thickens slightly.

Add the cooked spaghetti to the skillet with the sauce, tossing until each strand is coated. Use reserved pasta water if the sauce is too thick.

Gently return the cooked shrimp to the skillet, carefully combining to keep them tender. Finish with fresh basil.

Plate the pasta immediately, generously sprinkle with grated Parmesan, and add a drizzle of olive oil or fresh basil leaves for garnish.