Day 1: Peel, wash and roughly chop the garlic cloves. Soak the chopped garlic in vinegar, ensuring all of the garlic is submerged in the vinegar, cover and let it rest overnight.
Day 2: Blanch and peel the tomato. Chop it in a mush.
Grate the ginger into the vinegar-soaked garlic.
In a pan, heat mustard oil.
Add the mustard seeds and let them splutter.
Pour in the garlic ginger vinegar solution to the oil and cover immediately to stop the splutter and trap the fragrance (as my mother says).
Once the situation inside the pan is a little calm, uncover, add the tomato mush and give it a good stir.
Add the Nagaland Red Chilli Powder and a pinch of salt.
Give it a good stir and simmer for 10 minutes.
Let it cool completely before storing it in a glass jar.