Grease and line a 9” springform pan with parchment paper. Make sure you secure the lock. Keep aside.
Add saffron to warm water and keep aside to cool.
In another bowl sift all dry ingredients except sugar. Give it a quick mix.
In another bowl add sugar, yogurt, water, thandai powder, oil, rose water, and saffron water.
Whisk well with a manual or an electric balloon whisk until creamy and sugar has almost dissolved. Whisk, until the oil has emulsified well.
Slowly add dry ingredients to the wet ingredient bowl a little at a time.
Now whip everything until it forms a smooth batter. Do not over whip it.
Transfer it to the pan and bake it for 30-35 minutes or a toothpick inserted in the center comes out clean or with few moist crumbs.
Take out the cake from the oven and let it rest in the pan for 10 minutes.
Now gently run a butter knife through the circumference of the pan and release the pan carefully. Invert the cake on the cooling rack. Set the cake aside to cool.
Make the thandai mousse
Whipping the cream
Add chilled whipping cream, confectioner’s sugar, and a pinch of salt to a big bowl or a stand mixer. Whisk on a low speed for 3 minutes then whisk on a medium speed for 6-7 minutes.
Remember that the cream will double its size after whipping. Use a balloon whisk and not a beater to whip the cream to very loose and soft peaks. (Do not whip it to stiff peaks). Keep aside.
To activate agar agar
Add milk and heavy whipping cream to a saucepan. Sprinkle agar agar over it. Add in saffron, thandai powder, cardamom. Mix well to combine. Heat this mixture on medium heat stirring frequently. Once the mixture comes to a boil let it cook for a minute.
Switch off the flame and strain the mixture passing through a fine-mesh strainer. Let this mixture cool to warm. ( Do not cool the mixture completely or it will set before adding it to the cream. If the mix has cooled down for some reason, warm it up again until pourable consistency.
Important step to follow.
Now start whipping cream on medium speed with one hand and add the warm mixture to the cream with another hand and whisk continuously without stopping until soft peaks hold well.
This process of mixing will take only 10-12 seconds. So do not over whip. Scrape the sides with a spatula. Mousse consistency may look very soft, but it stiffens after chilling in the fridge. Remember that we want only soft peaks.
Assembling the cake
Line the circumference of the pan with an acetate sheet approx. 4” in height. (optional step). This helps smooth with the removal of the cake later on.
Slice the top dome of the cake to level it straight. Add the cake back to the springform pan. Make sure you lock the pan well. Scoop in the prepared mousse and level the top.
Cover the top loosely with foil and place it to set in the fridge for 6-8 hours or overnight.
After that, gently loosen the sides of the cake with a butter knife, unlock the springform pan and take out the acetate sheet.
Smoothen the cake on the top if needed. Add in some nuts and rose petals on the top.
Enjoy it straight out of the fridge.
Notes
About agar agar
There is no substitute for agar agar. I have used agar agar powder. You may use flakes.
Add agar agar to cold or room temperature cream. Do not add it to warmed cream as it will clump up. Warm up the cream after adding agar agar, not before that.
Do not let the agar cream mixture cool down before adding to the whipped cream. It should be warm and flowy consistency or it will set in clumps before whipping.
After whipping everything you may sometimes find very tiny bits of agar, it is completely fine and won’t affect the final taste or texture.
Agar Agar Conversion Guide 1 teaspoon agar powder = 1 tablespoon agar flakes=⅓rd cup agar strands cut into small pieces. Note that strands or flakes will take a minute more to dissolve well.
The texture of the whipped cream
For the mousse part, whip the cream only till very loose peaks form, almost like a thick milkshake consistency. Remember that we need to whip it more after adding the agar mixture.
Possible substitutes
Use parchment instead of an acetate sheet to cover the collar round of the cake. It will aid easy removal later on. If you do not have either of them then, simply run a knife around the circumference to loosen the edges.
I have used heavy whipping cream in this recipe. Look for a carton that says heavy whipping cream and not just heavy cream.
Swap Thandai powder for syrup.
Storage and Shelf life of this mousse cake
Thandai mousse cake needs to be refrigerated at all times and served chilled.
At a party, you can keep this cake out at the venue for 3-4 hours but in a cool place away from sunlight.
This cake keeps well in the fridge for up to 4 days
Some points to consider
Every thandai mix is not the same. If your thandai mousse doesn't have a strong taste then brush your cake sponge with some concentrated thandai milk for an additional kick.
Use a springform pan for this recipe.
Chill the entire cake in the fridge for at least 6-8 hours to set for a clean cut.