Heat the oil. Add the onions followed by the cardamom pods and saute over medium heat until the onions start to sweat and turn translucent.
Add the turmeric, cayenne and ginger garlic paste and stir-fry for 30 seconds.
Add the sweet potatoes, potatoes, and carrots. Season with some salt and cover the pan. Turn the heat to low and let the vegetables cook about five minutes. If the veggies start to stick, add some water.
Now add the green beans and green peppers and ½ cup of water or vegetable stock. Cover again and cook five more minutes.
Check to see if the potatoes and sweet potatoes are cooked and fork-tender. If they are not, continue to cook, covered, for a few more minutes.
Stir in the chickpeas, curry powder and another cup of vegetable stock. Bring the mixture to a boil.
Add the coconut milk and scallions, if using, and just let the curry heat through.
Stir in the lemon and cilantro and add more salt if needed. Serve hot.
