Prepare the Spices and Chicken: In a small bowl, mix together all the ingredients for the Cajun spice mix. Place the bite-sized chicken pieces in a larger bowl and toss them with 2 tablespoons of your spice mix until they are evenly coated. Set aside.

Cook the Pasta: Bring a large pot of salted water to a rolling boil. Add the pasta and cook according to packet instructions until al dente. Just before you drain it, scoop out and reserve about 250ml (a large mugful) of the starchy pasta water. Drain the pasta in a colander.

Sear the Chicken: While the pasta is cooking, heat the olive oil in a large, deep frying pan or sauté pan over a medium-high heat. Add the coated chicken pieces in a single layer (work in batches if necessary to avoid overcrowding) and cook for 5-7 minutes, turning occasionally, until golden brown and cooked through. Remove the chicken from the pan with a slotted spoon and set aside.

Sauté the Vegetables: Reduce the heat to medium. Add the chopped onion and sliced peppers to the same pan, using the residual chicken fat. Cook for 6-8 minutes, stirring occasionally, until the vegetables have softened and the onion is translucent.

Build the Sauce Base: Add the minced garlic and the remaining Cajun spice mix to the pan. Cook for one minute more until fragrant, stirring continuously to prevent the garlic from burning.

Create the Creamy Sauce: Pour in the chicken stock to deglaze the pan, scraping up any browned bits from the bottom with a wooden spoon. Allow it to bubble for a minute before reducing the heat to low. Stir in the double cream. What works best for me is to let it gently heat through without boiling, which keeps the sauce smooth.

Combine and Finish: Stir the grated Parmesan cheese into the sauce until it has melted and the sauce is smooth and glossy. Return the cooked chicken to the pan, along with the drained pasta.

Emulsify the Sauce: Add a generous splash (about 100ml) of the reserved pasta water to the pan. Toss everything together vigorously for a minute or two. The starchy water will help the creamy sauce cling beautifully to every piece of pasta. If the sauce looks too thick, add a little more pasta water until you reach your desired consistency.

Serve Immediately: Stir through most of the chopped fresh parsley. Serve the Cajun chicken pasta in warm bowls, garnished with the remaining parsley and an extra grating of Parmesan cheese.