Take a thick bottomed pan/sauce pan, add 2.5 cups of milk and bring to low flame.
Allow the milk to shimmer.
While milk getting heated, take a small bowl and add 3 tablespoon warm milk.
Either take it from pan or heat separately in microwave.
Add 3 tablespoon of custard powder to milk in ratio 1:1 and stir vigorously until the mixture becomes smooth without any lumps. Keep it aside.
Add 5 tablespoon of sugar to milk on stove, stir continously so that sugar dissolves completely in milk.
Take the custard pasted which is prepared previously, mix it into parts to milk on stove.
While adding mixture in parts, keep on stirring the milk to prevent forming of lumps until you finish the entire custard paste.
Now cook the entire mixture on low flame for 5-6 minutes, dont forget to stir continously to prevent lumps formation.
After some time the custard gets thicken slowly, if you want your custard to be thick then heat for some more time and off the stove.
Please note that after custard gets cool its gets more thick, so take care of time to heat.
Once its cools down keep custard in fridge to chill, after that you can add fruits to it.