Wash the lentils and rice thoroughly, you will probably need to rinse them both 5-6 times until the water runs clear. Then soak the lentils and rice for at least 30 minutes. Put the oven on 50-60 C, fan assisted.
Heat the ghee in the saucepan and add the onions. Cook the onions until lightly browned.
Add the boiling water to the pan, then add the drained rice and lentils to the pan and stir through. Next add the salt and cumin seeds. Stir through again. Cover with the pan lid and cook on medium heat, keep stirring gently at regular intervals to make sure the mixture is not sticking to the pan.
When around half of the water has evaporated from the pan, add half of the butter in the pan. Stir into the rice and lentils gently.
When the rest of the water has evaporated, add the remaining butter in lumps on top of the rice spread out as evenly as possible. Do not stir at this point. Let the butter melt into the rice and lentils. Then cover pan with the lid again.
Finally put the pan in the oven for 30 minutes to do dham (steam) the rice. This makes the rice and lentils have a lovely fluffy texture before serving. (You could alternatively do this on the hob, lift the pan lid and cover the pan with a thin tea towel. Put the lid over the top of the saucepan, make sure it is covered tightly. Then put the pan on the lowest heat on your hob and let it steam for 30 minutes).
Once the dham has been done, serve with a dollop of plain yoghurt, salted cucumber sticks, achar (pickle) and enjoy!