Take digestive biscuits in a mixer jar.Powder it finely.Set aside.
In a mixing bowl, add custard powder add 1/4 cup milk to it and mix well to make it smooth without any lumps.Set aside.
Take butter in a tadka pan and melt it.Add melted butter to powdered biscuits.
Mix well so that its moist and wet.Transfer the mixture to a spring form pan, flatten it using a flat bottomed bowl.Press it well.
It should be even and pressed tight.Refrigerate it for 30mins atleast.Meanwhile we can prepare the custard.Take 1 and 1/4 cups of milk in a pan.Boil it.
Add sugar to it.Whisk it well, now add custard powder milk mixture to it.
Whisk it for even mixing.Keep cooking until it forms a thick custard, the sauce will coat the laddle that is the correct stage.Switch off and allow it to cool down a bit.
Cut china grass into thin strips and add water to it.Boil it until the china grass is completely dissolved.Once dissolved completely, set aside to cool.
Take fresh cream in a mixing bowl.whisk it for a minute.Add prepared custard(it should be completely cool).
Mix well.Now add agar agar mixture(dont rest it for more time just 5mins or so then add it immediately).Mix well.
Immediately pour it into the pan.Cling wrap it and refrigerate it atleast for 4hours.Remove from pan,sprinkle chocolate shavings,cut it and serve.