Combine Cajun seasoning, 1 teaspoon salt, and brown sugar. Season chicken well and add to the hot pan. Cook until browned on both sides, about 3 minutes per side.
Remove chicken from pan and keep warm. Add onion (adding more oil if necessary) and saute until softened and starting to brown.
Add garlic, Italian seasoning and remaining ½ teaspoon salt and cook 1 minute.
Add broth, tomatoes and cream and bring to a simmer over medium-high heat.
Add dry pasta and browned chicken and bring to a boil (if your chicken is cooked through, you can also add it at the end). Cover and reduce heat so that the liquid is simmering, about medium-low. Stir often to prevent pasta from sticking.
If pasta is nearly ready but there is still lots of liquid left, simply remove the lid and finish cooking. This will help the sauce to thicken. When the pasta is cooked to desired tenderness, it's ready to serve.
Taste and adjust seasonings to taste, adding more Cajun seasoning if desired.
Leftover chicken works great in this recipe! Simply add the Cajun seasoning to the pasta (omit the brown sugar and salt unless needed) and stir in the cooked chicken before serving.
This pasta recipe is not as spicy as you might think (but it has great flavor!). If you're one who likes lots of spice, you may want to add 1 teaspoon Cajun seasoning or 1/4 teaspoon cayenne to the seasonings in the pasta.
The sauce might look thin at first but it does thicken as it sits. If needed, you can combine 1 teaspoon corn starch and 1 teaspoon water and stir in near the end of the cook time.
You can swap the penne for any short cut of pasta.
You can skip the chicken altogether for a vegetarian version (using vegetable broth), or swap it out for sliced Italian sausage, smoked sausages, or boneless skinless chicken thighs.
I don't recommend using any other cream in this recipe because it does not thicken and reduce the same way.