In a large pot, heat the olive oil over medium heat. Add the chicken pieces and sprinkle with Cajun seasoning. Cook until the chicken is browned and cooked through, about 5-7 minutes. Remove the chicken from the pot and set aside.

In the same pot, add the diced onion and bell pepper. Sauté for about 3-4 minutes until softened. Add the minced garlic and cook for an additional 1 minute until fragrant.

Add the whole wheat penne pasta, vegetable broth, and coconut milk to the pot. Stir to combine and bring to a boil.

Reduce the heat to a simmer and cover the pot. Cook for about 10-12 minutes, stirring occasionally, until the pasta is al dente and most of the liquid is absorbed.

Stir in the cooked chicken, cherry tomatoes, and fresh spinach. Cook for an additional 2-3 minutes until the spinach is wilted and everything is heated through. Season with salt and pepper to taste.

Serve hot, garnished with fresh parsley.