Chicken Spinach Pesto Soup

good quality olive oil

large carrots, peeled and cut into ¼ inch rounds

large clove of garlic, grated on a microplane

good quality, homemade chicken stock

marjoram

baby spinach, coarsely chopped

large bone-in chicken breast, roasted

cannellini beans or great northern beans, rinsed

good quality pesto

fresh ground pepper