Vietnamese Hot and Sour Soup

Serves: 2-4

• ½ onion- diced (1 cup)
• 1 tablespoon vegetable or olive oil
• 3-4 cloves garlic chopped
• 2 Cups sliced mushrooms (shiitakes or cremini)
• 4 Roma or vine ripened tomatoes- diced into 1 inch pieces
• 1 tsp sugar
• 1 tsp kosher salt plus more to taste
• ½ tsp fresh cracked pepper
• 4 cups vegetable or chicken stock
• 1 teaspoon soy sauce ( if using veggie stock)
• 8 oz firm tofu, cut into ¾ inch cubes
• 1 Tablespoon tamarind paste (or tamarind concentrate) or sub lime juice
• ¼   Cup chopped cilantro
• ¼ C chopped chives or scallions

Source: http://www.feastingathome.com/vietnamese-hot-and-sour-tamarind-soup/