First of all wash guava and tomato thoroughly. Cut guava and tomato into small pieces and keep them in separate plates. Remove the seeds from guava. Heat oil in a pan. When the oil is hot, add cumin seeds. When the cumin seeds crackle, add green chillies, ginger paste and asafoetida and fry for some time. Now add guava pieces, red chilli powder, turmeric powder, coriander powder and salt and mix well. After this add water to it