Remove the thick green corners of the plantain and wash it well. Cut it into medium-sized cubes and soak in water immediately to avoid blackening.
Grind the grated coconut, green chillies and cumin in a grinder to a nearly fine paste.
Add the sour yoghurt to this coconut mixture and grind into a smooth paste.
In a pan, add the cubed plantain and 1.5 cups of water. Mix in the turmeric powder and 1 tsp of salt. Close the pan with a lid and let cook on medium flame until the plantain becomes soft enough. The plantain consistency should not become too mushy.
Once the plantain is cooked, pour in the coconut and yoghurt mixture. Stir the curry well so the flavours are incorporated. Check if more salt is needed at this stage. Let boil once and turn off flame.
In another small pan, heat 2 tsp of coconut oil.
When the oil is hot, splutter the mustard, then follow up by adding the dry chillies and curry leaves. Stir slightly until just browned (10-15 seconds) on low flame and add into the plantain broth.
Mix everything well and close the dish with the lid for 10 minutes so that the aroma of the curry leaves and coconut oil spreads evenly throughout the dish.
