Recipes: Black bean burgers

Preparation:        Preparation time: 5 mins  Cooking time: 10 mins  Serving: 6 Ingredients: 400g tin black beans or kidney beans, drained 2 tbsp light olive oil, or 30g butter, for cooking 1 medium red onion, finely chopped 140g mushrooms, finely chopped 2 tbsp tamari (for gluten-free option) or soy sauce 1 clove garlic, finely chopped 1...