Take a small bowl and add in 2.5 tablespoons of vanilla flavored custard powder
Add in half a cup of cold milk and mix it well until there are no lumps and the consistency is even
Keep the bowl aside for later use
In a saucepan, add 500 ml of milk and heat it on a medium to low flame
Add 20-30 grams of sugar and mix well, let the milk start to boil
As it starts boiling, add in your custard slurry slowly while gently stirring to avoid any lumps
Cook your custard for 1-2 more minutes on medium flame until it has a thick but runny consistency
Remove your custard from the stove and set aside to cool down
Stir it lightly to cool the custard down
Use a cookie cutter or a lid of any jar to cut out the circular shapes from the bread slices
Take a circular slice, add your bread filling on it, top it off with crushed nuts
Add another slice on top to make it into a sandwich and add your bread filling on it as well
Garnish with nuts, mango chunks and add another slice on top making it a three-layered sandwich
Dish out the custard, add in your remaining cup of mango puree in it and mix well
Add the bread sandwiches on a tray and pour your custard mixture over it
Garnish with mango chunks, and sprinkle crushed nuts over them
Chill in refrigerator for a few hours before serving