Bring the rice, coconut milk, coconut powder and water to the boil, making sure you stir it at regular intervals. (The glutinous nature of the rice in combination with the coconut causes it to catch and burn quickly over high heat.) Reduce the heat to the lowest simmer possible, put the pot lid on and continue to cook, stirring intermittently until the rice is cooked. This should take approximately 15 minutes. As with all rice, it is done when just cooked through or al dente.
Add the salt and mix thoroughly. The rice may seem overly salty at this point but in conjunction with the other ingredients it will be perfect. Trust me!
For the umeboshi filling, mix together the umeboshi and palm sugar.
While still warm, shape some of the rice into a disc approximately the diameter of a ping pong ball (approx. 35g). Spoon a little mixture in to the centre, then shape in to a ball by pulling up the circumference of the disc and gently push the rice together so that the umeboshi is completely encased.
Continue this process until all of the rice and umeboshi has been used up.
To cook, roll the rice balls in desiccated coconut then deep-fry in vegetable oil until golden brown.
For a dry caramel, warm a pan gently over a medium heat for a few moments then place the sugar in the pan, still over a medium heat. Leave the sugar like that, keeping an eye on it, until it begins to melt.
Once the sugar begins to melt and caramelise around the edges, stir with a slotted spoon regularly until a consistent golden colour is achieved.
Take off the heat and slowly pour in the cream. The sugar will cease up but return to the heat and stir until the sauce is homogenous again.
Lastly whisk in the tamarind.
Serve the rice balls with the caramel and wedges of lime.