In a big bowl add in the graham cracker crumbs, sugar and melted butter. Mix it with your hand.
Take a baking tray lined with parchment paper, add the crust mixture to it. Spread it evenly.
There are two ways to use this crust, either bake it at 350 degrees F for 8-10 min (till they turn golden brown), or compact the crust really well using ant too (glass tumbler used here) and refrigerate for 30 minutes and the crust would settle down.
For the filling, first mix the corn starch into the lemon juice (fresh), mix it well.
In another pan, Mix the water and agar powder, mix it well and bring it to a boil. Cook on medium to low heat for 2-3 min till it thickens (happens quickly – do not leave unattended).
When the mi is thick add the sugar and cook till sugar dissolves (1-2 min).
To this add the starch and lemon juice mix, with lemon zest and turmeric or food color. Then add the milk/cream.
Once done, before it settles, pour it over the crust. Let the mixture cool down then refrigerate for 2-3 hours, or till the lemon mixture sets.
Lift the whole recipe out using parchment paper, dust with powdered sugar, cut and serve!