Heat the oil in a large pan and add mustard seeds. When it starts to pop add urad dhal and fry until golden. Add red chilies. Then add the onions and tomatoes and fry until the onions are soft. Then add the carrots, peas, turmeric powder and salt. Saute until the vegetables are tender. Pour 2 1/4 cups of water to this. When it boils add the rava slowly and keep stirring to prevent from lumps forming. Cook until the rava is cooked and all the water is absorbed. Garnish with chopped coriander leaves.