Thinly slice the salad onions and the runner beans.
Heat the oil in frying pan over low heat and gently sauté the salad onions and garlic for a minute or so.
Add the runner beans, soy sauce, lemon juice and vegetable stock. Put a lid on and cook over low heat for about 3-5 minutes until the beans are tender.
Take a spoonful of the cooking jus into a small bowl. Add the miso and sesame oil and mix well until you get a smooth paste. Pour this over the beans and toss gently.
Serve warm with sesame seeds scattered on top.