In a thick bottomed pan heat the milk stirring occasionally. Take care the milk should not burn. You can drop a small ceramic plate this helps in preventing the burnt smell to the milk. Now that does not mean you should stop occasionally stirring the milk.
As the milk is thickening make a fine powder of the almonds, khus khus, fennel seeds and cardamom. Set aside.
Once the milk thickens and reduces to about 4 cups tip in the sugar and stir well. The milk will become a bit watery but that is okay, continue heating it to reduce to 4 cups.
Add the saffron. Mix well.
Add the Thandai powder blend it.
Cool and refrigerate for minimum 2 hours.
You can strain the milk if you wish but I prefer not to.
Pour into glasses and serve.