Heat butter; sauté shallots and ginger with cumin seeds and bay leaves. Add tomatoes; stir for a couple of minutes. Pour stock and add potato and carrot pieces. Simmer over low heat till both are half cooked. Add caulis and French beans. Continue to simmer till veggies are soften (to a texture you prefer) Season with pepper and salt. Off the heat and garnish with spring onions and coriander leaves before serving.