Soak the kokum petals in 4 tablespoons water with ¼ teaspoon salt for 20 minutes.
In a mixer grinder, add all ingredients except the soaked kokum. Grind with 1 cup water, adding ¼ cup more if too thick.
Strain to extract the coconut milk, discarding the solid pulp. Add ¼ cup more water while straining for a milk-like consistency.
Add the soaked kokum petals along with their water.
Adjust salt to taste.
Garnish with chopped coriander leaves and serve with rice.
Notes
Never reheat kokum kadi directly on the stove — the coconut milk fat will separate.
If you'd like it warm, temper 1 teaspoon coconut oil and 1 teaspoon mustard seeds until spluttering, then pour over the freshly made kadi.