2 (1 pound) sweet potatoes, quartered
1 large tart apple, peeled and cored
2 tablespoons olive oil
1 onion, chopped
2 stalks celery, chopped
1 large carrot, chopped
1 bay leaf
5 cups chicken broth
1 cup cream
1 (5 ounce) lemon, zested and juiced
salt and pepper to taste
1 cup crumbled goat cheese or feta cheese