Grind the soaked whole wheat in a mixer or wet grinder to a fine puree adding water as needed. Strain this puree and squeeze to extract it's thick juice.
Once again add the squeezed wheat puree in to mixer and grind finely adding a cup of water. Re-strain the puree and extract the juice completely discarding the residue.
Pour this strained puree in to a vessel and add one more cup of water. Let this vessel sit for 2 hours so that the thick wheat puree settles down. Carefully discard the floating plain water and reserve only the thick puree.
Heat a thick bottom wok adding jaggery and half cup of water. Let the jaggery dissolve completely. Meanwhile grind grated coconut to fine paste adding half cup of water.
Combine coconut paste and wheat puree from step 3 with the dissolved jaggery in the wok. Also add 2 cups of water and cardamom powder. In medium flame cook this mixture stirring continuously with a ladle.
When the mixture turns little thick add some ghee and continue stirring. The process of stirring and adding ghee every now and then should continue for about 40-50 minutes. The mixture turns in to thick porridge consistency and it will not stick to your teeth when you chew. That is the stage when you have to switch off the flame.
Grease a tray with little ghee and pour the wheat halbai mixture in to it. Let it cool down and then you can mark pieces using sharp knife.
Very soft and melt in mouth textured wheat halbai is ready to serve.