Season the chicken pieces with salt, pepper, and Italian seasoning. Heat olive oil in a large skillet or Dutch oven over medium-high heat. Add the chicken and cook until golden brown and cooked through, about 5-7 minutes. Remove the chicken and set it aside.

In the same skillet, melt the butter. Add the chopped onion and cook until softened, about 3 minutes. Add the minced garlic and cook for another minute until fragrant.

Add the halved cherry tomatoes to the skillet. Cook for 4-5 minutes, pressing down on them gently with a spoon to help them burst and release their juices.

Pour in the chicken broth and bring to a simmer. Stir in the dry pasta, ensuring it's mostly submerged. Cover the skillet, reduce the heat to medium-low, and let it cook for 10-12 minutes, or until the pasta is al dente, stirring occasionally.

Uncover the skillet and stir in the heavy cream, grated Parmesan cheese, and cooked chicken. Cook for another 2-3 minutes, allowing the sauce to thicken.

Turn off the heat and stir in the fresh spinach until it wilts. Taste and adjust seasoning with more salt and pepper if needed. Serve immediately.