Greens 'n' Beans Soup

2T extra virgin olive oil
1 large sweet onion , chopped
3 stalks celery, coarsely chopped
2 carrots, coarsely chopped
2 cloves garlic, left whole
2 heads escarole, tough outer leaves removed, cut into 1" pieces
2 C small white beans, soaked overnight
4 C chicken broth
salt and pepper to taste

Heat the oil in a skillet over medium heat. Add the onion, celery and carrots and saute until the onion begins to soften. Add the garlic and continue to cook for 2 minutes. Transfer the contents to a slow cooker. ( I added 4 chicken breasts on top of this) Add escarole, beans and broth. Season with salt and pepper. Cover and cook on high for 4 hours.  Serve the soup garnished with Parmigiano- Reggiano.