In a large pot, bring salted water to a rolling boil over high heat. Add fettuccine or spaghetti and cook according to package instructions until al dente, about 8-10 minutes. Drain the pasta and set aside, reserving a cup of the pasta water for later use if needed.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the diced onion and minced garlic, sautéing for 2-3 minutes until fragrant and translucent.

Stir in the sliced red bell pepper and cook for another 2 minutes. Add the large shrimp, stirring frequently for 3-4 minutes until they turn pink and opaque.

Lower the heat to medium-low and sprinkle in the Jamaican jerk seasoning. Pour in the coconut milk and heavy cream, mixing well and letting it simmer gently for about 5 minutes.

Gently add the drained pasta to the skillet, tossing to coat thoroughly in the creamy sauce. Cook for an additional 2-3 minutes, adding reserved pasta water if needed.

Adjust seasoning with salt and black pepper to taste, and fold in the chopped fresh parsley. Serve hot, garnished with lime wedges and grated Parmesan cheese if desired.