In a pan put 1 tsp of oil, then put one red chili then mustard seeds. When they splutter, add chanadal and urad dal. Fry till they are light brown then add turmeric and curry leaves and jeera. Add the cut onions and salt to taste. Fry till they are light brown. Then add tomatoes and cook till they are tender. When these cool add avocado pieces and mix well. Next add yogurt and mix. Serve with chopped cilantro.