First start heating milk in a heavy bottomed vessel, grease the bottom of the pan with few drops of ghee.(this is to prevent burning  of milk at the bottom). Take 2 tablespoons of warm milk and keep saffron soaked till needed.

Boil milk for 20-30 minutes in very low flame. Keep stirring now and then.

When the volume reduces almost half,add the saffron soaked in the milk,evaporated filled milk and boil for 2 more minutes.

Chop the nuts and fry it in ghee till golden brown and add it to the milk too,add the sugar and simmer for few minutes. (Is this is called rabri/rabdi)?.

Squeeze the sugar syrup from the rasgullas,take care you don't squeeze the rasgullas hardly(this will make the rasgulla break),just squeeze it gently.

Add it to the milk when it is still hot. Let it get soaked. After cooled down,refrigerate and serve cold.