In a small bowl mix together custard powder and ½ cup milk till smooth.
Heat the remaining milk in a heavy bottom pan. Then add sugar and stir to dissolve completely. Taste in between and adjust sugar to taste.
Now pour in the custard milk at a slight height (to avoid lumps) whilst stirring the milk in the pan constantly with a hand whisk. Stir till thick and of custard consistency.
Consistency should be such that it coats the back of a spoon and you are able to draw a line. This process takes about 2 to 3 mins.
Remove from heat and add vanilla essence. Let cool till just warm.
Prepare the coffee decoction. Take a 8”x8” flat glass dish (or any shape/ size as per choice). Dip each of the biscuit in the coffee solution 1 to 2 seconds and arrange in the dish in a single layer as the base.
Top it with a layer of some of the prepared custard. Repeat the layer 2 or 3 more times to get 3 to 4 layers.
Let chill in the fridge for minimum 4 hours or even overnight.
Garnish/ decorate with your favourite toppings, cut into squares and serve!
Note
Beat the custard once lightly just before you layer it to loosen it up a bit. If you feel the custard has become too thick, add a tbsp or two of milk & beat once with hand whisk.