Rinse the shrimp, pat it dry with a paper towel and place it in a bowl. Sprinkle one tablespoon of cajun seasoning over the shrimp and gently toss to coat.
Heat the olive oil and butter over medium heat in a large skillet then drop in the shrimp and saute 1-2 minutes per side without overcooking them then remove them from the skillet and reserve.
Reduce the heat to low then add the onion, bell peppers and grated garlic to the same skillet. Season it with 1/4 teaspoon of the cajun seasoning and cook 2-4 minutes or until the onions have softened, stirring frequently so the garlic doesn’t burn.
Meanwhile cook the pasta one minute less than package directions. The pasta will finish cooking in the sauce. Scoop out 1/4 cup of pasta water then drain the pasta.
Add the pasta water to the skillet along with the wine, (undrained) can of diced tomatoes, smoked paprika, Worcestershire sauce and the other tablespoon of Cajun seasoning. Simmer 5 minutes over medium-low heat letting the sauce thicken slightly.
Taste the sauce and adjust for salt and heat (I added a light sprinkle of both salt and cajun seasoning.
Add the cooked pasta to the sauce, tossing to coat it and continue cooking the pasta in the sauce 2 minutes. Return the shrimp to the skillet, fold in the parsley and serve right away with slices of lemon for squeezing over the top.