Cut the bread slices in square pieces. If you are using fresh bread then do not cut the corners of it. if you are using few days old bread then remove the sides of it.
Put 1 tablespoon cooking oil in pan and let it heat.
Add ½ teaspoon of brown mustard seed and let them crackle and pop.
After then add ½ teaspoon of cumin seed and let them crackle and cook it until its color changes to light brown
Add green chilies and ginger in it and saute it until raw aroma of ginger and chilies goes away,
Add chopped onion on it and saute the onion until it changes its color little bit.
Now add chopped tomatoes and saute it.
Add 1 pinch of turmeric powder, 1 teaspoon of chaat masala, You can add red chilly powder to increase the spiciness of dish. It is completely optional.
After adding all the spices, mix it very well. Add salt according to your taste.
Stir and saute all onions, tomatoes and spices. Within few time tomatoes will be soften and you will see the released oil from the sides. Tomatoes need to cook well for removing the raw flavor of it, otherwise it will not taste good.
Add all the vegetable which we are using boiled potatotes cut into pieces, boiled peas, chopped capsicum.
Cook these for few minutes. If you are using boiled vegetables then mix it well with spices. If you are using raw vegetables then cut into small pieces so that they can cook in less time. Cook raw vegetables for 3 to 4 minutes. And add little bit of water in it for cooking them.
Add little bit of water and boil it.
Now add bread pieces and mix it well.
Serve it on plate and add some lemon juice on top of it.