Heat olive oil in a large skillet over medium-high heat.
Add chicken pieces, season with salt and pepper, and cook until golden brown, about 5–6 minutes. Remove from skillet and set aside.
In the same skillet, sauté onion and garlic for 2–3 minutes until fragrant.
Add cherry tomatoes and cook for another 2 minutes until softened.
Pour in chicken broth and heavy cream. Bring to a simmer.
Add gnocchi and cook for 4–5 minutes until tender.
Return chicken to the skillet, add spinach, and stir until wilted.
Mix in Parmesan cheese until sauce thickens slightly.
Taste and adjust seasoning. Serve hot, garnished with fresh basil or parsley if desired.