Minestrone with Kale and mixed grains

Ingredients

• 1 onion or leek, diced
• 2 garlic cloves, finely chopped
• ½–1 tbsp olive oil
• ¼ cup each of red, white and black quinoa
• ¼ cup brown rice
• ¼ cup barley
• 1 tsp dried oregano
• 1 bay leaf
• 400 g tin chopped tomatoes
• 2 cups vegetable stock
• 300–500 ml filtered water
• 1 cup green beans, chopped into 1-cm pieces
• 1 carrot, diced
• 2 cups finely chopped kale
• 1 tbsp fresh oregano, chopped
• 2 tbsp grated lemon zest (optional)
• 2 spring onions, finely sliced (to garnish)