In a pressure cooker pan add ghee and cumin seeds and sauté until cumin seeds are brown. Add chopped onions and sauté for a minute. Add vegetables and mix and let it cook for couple of minutes. Add tomatoes and mix. Once mixed add moong daal and add salt, turmeric and chilli powder and mix. Lastly add oats and mix and add 3 cups of water and let it cook for 3 whistles or if cooking without pressure cooker cook for 15 to 20 minutes stirring occasionally.