Pat the chicken dry and season both sides with Italian seasoning, salt, and pepper. Prepare the vegetables or sausage if the recipe includes them.
Heat olive oil in a large skillet over medium-high heat and cook the chicken until golden and cooked through. Transfer it to a plate.
Cook the garlic and the asparagus, sausage, or other added ingredients as needed until tender and lightly browned.
Add chicken broth, heavy cream, Parmesan, sun-dried tomatoes, and Italian seasoning. Stir and simmer until the sauce becomes creamy.
Return the chicken to the skillet and spoon the sauce over it. For the mozzarella version, add the mozzarella and let it melt into the sauce.
Let everything cook together for a few minutes so the chicken absorbs the sauce and the added ingredients are heated through.
Taste and adjust the seasoning, then serve warm with the creamy sauce.