Crush the garlic and cumin seeds together using a mortar and pestle until coarse.
Heat mustard oil in a pan and sauté the crushed garlic-cumin mixture until golden brown.
Mix the Kashmiri chilli powder with water to form a smooth slurry.
Add the chilli-water mixture and salt to the pan. Bring it to a rolling boil and let it simmer for a minute
Whisk the curd until smooth, making sure the whey does not separate.
Reduce the heat to low, add the whisked curd, mix well, and immediately turn off the stove.