1 T olive oil
1 large onion, diced small
1 tsp. minced garlic
3/4 tsp. ground coriander
3/4 - 1 tsp. ground cumin (I used a whole teaspoon, but I love cumin)
1/4 tsp. ground fennel
fresh ground black pepper to taste
1 large or 2 medium sweet potatoes, cut into 1/2 inch piece
2 cans (15 oz. can) black beans, rinsed and drained
4 cups homemade vegetable or chicken stock (or use 3 cans broth and just freeze the extra)
salt to taste
2 T fresh-squeezed lime juice
fat free Greek yogurt or light sour cream for serving
lime wedges to squeeze into the soup, optional