When cooking the curd, always do it on a double boiler. Never cook the curd over direct heat as the heat can burn the curd. Even on a double boiler, keep stirring and scraping the bottom of the bowl until mixture until it thickens. This is to avoid the eggs from getting lumpy in the curd. If you do not have a double boiler, you can make one. Pour some water (about 2 or 3 inch height of water) into a small pot and place a heatproof bowl (stainless steel metal bowl or glass bowl) on top. Make sure the bowl is larger than the pot so that it rests on the rims of the pot and does not touch the water. Turn on the heat and the the steam from the hot water heat up the bowl and cook the curd.