How to Make It
In a medium saucepan of boiling salted water, cook the green beans until crisp-tender, about 3 minutes. Using a slotted spoon, transfer the beans to a colander and rinse under cold water. Repeat with the carrots, cooking them until barely tender, about 5 minutes. Repeat with the bell pepper, cooking it for about 1 minute. Add the potatoes to the saucepan and boil until tender, about 10 minutes. Drain the potatoes and cut them into 1-inch chunks.
Heat the oil in a large skillet. Add the garlic, ginger, green chile and cumin seeds and cook over low heat until fragrant, about 3 minutes. Add the scallions and onion and cook until softened, about 5 minutes. Add the tomato, season with salt and cook over moderate heat until the liquid evaporates, about 2 minutes. Add the vegetables, coriander, pepper and turmeric and season with salt. Cook, stirring, until the vegetables are heated through, about 3 minutes. Serve hot.