1. In a heavy bottomed wok, put oil and heat it till hot (not smoking).
2. Add Mustard, allow to splutter.
3. Add onions fry till translucent.
4. Add tomatoes, cook without adding water as the tomatoes will give out enough water to cook.
5. Cook mix till semi solid.
6. Add water if and only if necessary.
7. Add the rest of ingredients, mix well on low heat.
8. Take wok off fire.
9. Apply mix to a slice of bread to make a sandwich.
10. Heat the sandwich in a sandwich maker.
11. Enjoy hot or cold!

Variation:
We can add carrots or any vegetables of our choice to make it more healthier.