Clean and soak the dry tapioca overnight. Wash well and pressure-cook with a ¼ spoon of turmeric powder and salt. Grind together coconut, garlic, ginger, green chillies, jeera, a few curry leaves, ¼ spoon turmeric powder and salt with ¼ cup of water. Add this masala to the tapioca, close with a lid and cook on low flame for 5 minutes. In another pan, heat coconut oil. Splutter the mustard seeds. Add in the dry red chillies and curry leaves. Remove from the flame as soon as the chillies turn brown. Pour this into the tapioca mix and close the lid. Let it remain for 10 minutes. Serve hot with ullichammanthy (grind shallots, tamarind, red chillies, coconut oil and salt) and fish or meat curry.