Over medium low heat, sauté the onions and garlic in the olive oil until browned.
Add the tomato paste and stir making sure that the paste does not burn.
Add the chicken stock and scrape the browned bits from the bottom of the pan.
Add the beans, seasonings, and spinach. Cook until most of the liquid has cooked
off and until heated through. (Approx 15 minutes)
Add proscuitto. Stir to combine. Remove from heat.