Pre heat oven to 350ºF. Soak semolina in 1 cup half and half or whole milk till it gets soaked well for 10 minutes.
Grind the almonds with half the sugar in the food processor till reduced to a fine powder. Transfer to a bowl.
Cut the Unsweetened khoya (Nanak Khoya or Bapu ka Khoya) into small cubes. Pulse and blend them in the food processor with the remaining sugar until reduced to powder. Transfer everything to the bowl with the ground almonds.
Soak the semolina in milk and mix well with a whisk or spatula to combine everything well without any lumps. In order to get a grainy texture which is desired it is recommended to mix it manually. By pulsing it with the other ingredients, the coarse grainy texture of the semolina is lost and the dum ka rote gets a pasty texture.
Add the ghee to the blended almond khoya mixture in the bowl followed by the soaked semolina and combine everything well.
Transfer this mixture to a heavy bottomed sauce pan or non stick pan and on steady medium low heat keep stirring till it starts bubbling and thickening slowly. Finally add saffron water( crushed saffron soaked in 1tbs of hot water) and mix well. Do not raise the flame or stop stirring at this stage as it could quickly get burnt at the bottom. Once it thickens enough it starts leaving the sides, therefore it is time to switch off the stove and stop cooking.
Grease a baking dish with ghee and pour the thickened halwa into it. Garnish the halwa with slivered almonds and melon seeds on top. And as a finishing touch sprinkle some crushed saffron too. Place it in the centre of the preheated oven and bake for 30-35 minutes until the layers at the top and at the base start browning and the sweet scented aroma of saffron is filling the air.
As the halwa is baking in the oven, it slowly starts browning at the top and bottom and the sides become crusty and crunchy which is the best part of the halwa. Once this magic happens it is a signal that the halwa is done just right and should not be left in the oven any longer as too much darkening gives a bitter taste to it.
Remove from the oven and let it cool down to room temperature.
You can decorate the halwa with silver paper and serve it warm to your guests for dessert. You could warm it in the microwave too just before serving it. Enjoy!