In a large pot, heat the oil over medium-high heat. Add the onion and cook, stirring, until it begins to soften, about three minutes. Add the garlic and cook until it becomes fragrant, about 30 seconds. Add the chicken and broth. Bring the mixture to a boil and add the gnocchi. Stir in the peas and carrots. Add the spinach and season with salt and pepper to taste. Continue to cook until the spinach has wilted, about two to three minutes.
Serve immediately or store in the refrigerator for up to three days.