Heat 1 tablespoon of olive oil in a large deep skillet or Dutch oven over medium heat. Once shimmering, add sliced kielbasa and brown for about 5–7 minutes.

Toss in the finely diced onion and cook for an additional 3–4 minutes until soft and translucent.

Sprinkle in Cajun seasoning, salt, and add minced garlic. Stir for about 1 minute until fragrant.

Add canned chopped or crushed tomatoes (with juice) to the skillet and stir until blended. Incorporate dried pasta evenly.

Pour in 4 cups of hot chicken stock. Bring to a boil, reduce to a simmer, and cover for 12–15 minutes until pasta is tender.

Remove from heat, fold in mascarpone and grated Parmesan cheese until melted and creamy.

Fold in fresh basil leaves and adjust seasoning with salt and pepper if necessary.

Serve hot, garnished with extra Parmesan and a sprinkle of chili flakes if desired.