Break the bread slices into smaller pieces with or without the crust. Heat oil in a kadai. Add a pinch of asafoetida. Add cumin seeds and mustard seeds. When the cumin seeds change colour and mustard seeds crackle, add onion and sauté. When the onion turns translucent, add diced potatoes and sauté for two minutes.
Add turmeric powder and bread pieces. Mix and add red chilli powder and toss to mix well. Sprinkle some water and cook for two minutes. Add lemon juice, green chillies and coriander leaves. Toss and serve hot.