Put the beans and thyme into a saucepan of lightly salted water and boil vigorously for about 45 minutes, until the peas are soft.
Allow the boiled kettle water to cool a little then pour over the desiccated coconut in a bowl to make coconut water.
Put the desiccated coconut and boiled water into a blender or food processor and blend, then strain. Discard the coconut.
Add the rice and coconut water to the soft peas in the saucepan.
Put a lid on the saucepan, turn the heat down very low and leave the rice to cook. It will take approximately 40 minutes.