Season and sear the chicken: In a bowl, toss the chicken strips with 1 teaspoon of the Cajun spice blend (mix the smoked paprika, oregano, garlic powder, cayenne, black pepper, and salt together). Heat 1 tablespoon of olive oil in a large, deep skillet or Dutch oven over a medium-high heat until it shimmers. Add the chicken in a single layer—you should hear a vigorous sizzle. Cook for 3–4 minutes per side until the strips are deeply golden brown and the kitchen smells wonderfully smoky. The chicken should feel firm to the touch and release easily from the pan. Transfer to a plate and set aside.

Sauté the aromatics and peppers: In the same pan, reduce the heat to medium and add the remaining tablespoon of olive oil. Tip in the chopped onion and cook for 4–5 minutes, stirring often, until it turns translucent and softens, releasing a sweet, fragrant smell. Add the minced garlic and sliced bell peppers, and cook for another 3–4 minutes. The peppers should start to soften and the garlic should become aromatic but not browned.

Build the Cajun sauce base: Sprinkle the remaining Cajun spice mix over the vegetables and stir constantly for 30–45 seconds. You'll notice the spices darken slightly and release an intense, smoky aroma. Add the tomato purée and stir for 1 minute. The mixture will become a deep, rich brick-red colour. Pour in the chicken stock, scraping the bottom of the pan with a wooden spoon to lift any browned bits—this is where immense flavour hides. Let the sauce come to a gentle bubble.

Cook the pasta: While the sauce base develops, bring a large pot of generously salted water to a rolling boil. Add the penne and cook according to the package directions until al dente. Just before draining, reserve a mugful (about 250ml) of the starchy pasta water. The water should look cloudy and feel slightly slippery between your fingers—this starch is liquid gold for your sauce. Drain the pasta in a colander, but do not rinse it.

Finish the creamy sauce: Pour the double cream into the simmering sauce base and stir gently to combine. The colour will shift to a beautiful, warm coral. Bring the sauce to a gentle simmer—you should see small bubbles lazily breaking the surface, not a violent boil. Let it cook for 2–3 minutes, stirring occasionally, until it thickens slightly and coats the back of a spoon.

Combine everything: Return the seared chicken and any collected juices to the pan. Add the drained pasta and a splash of the reserved pasta water (start with 100ml). Toss everything together using tongs, ensuring every piece of chicken and pasta is coated in the luscious, creamy sauce. If the sauce seems too thick, add more pasta water a tablespoon at a time until it reaches your preferred consistency. The sauce should cling to the pasta but still flow loosely.

Add the cheese and rest: Remove the pan from the direct heat. Sprinkle over the grated Parmesan and gently fold it through the pasta until it melts into the sauce, creating an even silkier texture. Let the dish sit, covered, for 3–4 minutes. This brief rest allows the flavours to meld together and the sauce to settle perfectly onto the pasta. The pan should still be warm, and the sauce will look glossy and inviting.

Serve immediately: Divide the pasta among warm bowls, ensuring each portion gets a generous amount of chicken and peppers. Garnish with a sprinkle of fresh parsley and an extra crack of black pepper if desired. The first forkful should deliver a creamy, smoky, and gently spicy sensation.