Season chicken with salt, pepper, paprika, and Italian seasoning. Heat olive oil in a large pot over medium heat and sear chicken 4–6 minutes per side until about 70% cooked. Remove, chop, and set aside.
In the same pot, melt butter. Add shallot and garlic; sauté until soft and fragrant.
Stir in Parmesan and Boursin cheese until melted. Slowly add heavy cream and chicken broth, stirring constantly.
Add chicken back to the pot and simmer 6–8 minutes until fully cooked.
Stir in noodles and cook 10–12 minutes, stirring occasionally, until tender.
Add broccoli, mozzarella, and parsley. Stir until melted and creamy. Adjust seasoning and add broth if needed. Serve warm.