Preheat oven to 400ºF.
Take the head of garlic and chop just enough off the top to expose the cloves. Drizzle with EVOO, wrap it in tin foil and bake for about 45 minutes to an hour.
Meanwhile, heat a soup pot over medium to medium-high heat with 2 tablespoons EVOO. Add celery, onion, carrots, season with salt and pepper, and cook 5 minutes. Add crushed tomatoes and 4 cups water to the pot, cover and bring to a boil.
Remove garlic from oven and squeeze the roasted cloves out into the bowl of a food processor. Add 1-1 1/2 cups of soup and puree till smooth. Add garlic broth back to the stoup and cook for 5 minutes.
Place ground chicken in a bowl and season with salt and pepper. Add egg, breadcrumbs and cheese. Combine the chicken mixture with your hands then roll into walnut-sized meatballs. Heat a medium skillet over medium-high heat with the vegetable oil and brown the meatballs. Add the browned meatballs to the soup and cook for 10 minutes.
Wash up, then add the gnocchi to the pot and cook for 5 minutes more. Turn the heat off under the stoup and let cool for 5 minutes on the stovetop before serving.