Let’s get cooking! Follow these steps to bring this comforting dish to life:

1. Preheat your oven to 350°F (175°C).
2. Cook the pasta shells according to the package instructions until al dente. Drain and set aside.
3. In a large skillet, heat olive oil over medium heat. Add the diced onion and cook until translucent, about 5 minutes.
4. Add the minced garlic to the skillet and sauté for an additional 1 minute until fragrant.
5. Stir in the shredded chicken and Cajun seasoning. Cook for another 2-3 minutes, allowing the flavors to meld.
6. In a medium bowl, combine the ricotta cheese, half of the mozzarella, and half of the Parmesan cheese. Mix in the chicken and onion mixture until well combined.
7. Spoon the chicken and cheese mixture into each pasta shell, placing them in a single layer in a baking dish.
8. In a separate saucepan, heat the heavy cream over low heat. Stir in the remaining mozzarella and Parmesan cheese, cooking until the cheese is melted and the sauce is smooth.
9. Pour the cheese sauce over the stuffed shells in the baking dish.
10. Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and golden.
11. Garnish with fresh parsley before serving, if desired.

Remember, the key to this dish is not rushing the process. Take your time to let the aromas fill your kitchen, and don’t be afraid to taste as you go to adjust the seasoning to your preference.