In a large pot of salted boiling water, cook the fettuccine according to package instructions until al dente. Drain and set aside.
In a bowl, toss the chicken pieces with Cajun seasoning until well coated.
In a large skillet, heat 2 tablespoons of olive oil over medium-high heat. Add the seasoned chicken pieces and cook for about 5-7 minutes, or until golden brown and cooked through. Remove from the pan and set aside.
In the same skillet, add the chopped onion and bell pepper. Sauté for 3-4 minutes until they soften. Add the minced garlic and cook for an additional minute until fragrant.
Pour in the chicken broth and let it simmer for 2-3 minutes. Then add the heavy cream and stir well to combine. Bring the mixture to a gentle simmer.
Return the cooked chicken to the skillet and add the cherry tomatoes. Let everything simmer for an additional 3-4 minutes. Stir in the cooked fettuccine, and toss everything together until well combined.
Remove from heat, stir in the grated Parmesan cheese, and season with salt and pepper to taste.
Garnish with chopped fresh parsley before serving.