Take milk in a heavy bottomed vessel and bring it to a boil.
Keep stirring continuously and reduce milk to 1/3 of its volume.
At this stage add about 1 tsp of lemon juice and continue stirring.
After adding lemon juice add sugar and continue to stir for about 15 to 20 minutes.Milk halwa gathers as a mass and if you stir, it will swirl in the pan.Transfer it to bowl (you can even transfer to a plate and cut them into pieces)
Little words
Add cardamom /elaichi powder for flavour.
Keep stirring throughout the entire process to get a nice textured halwa(and to avoid burning).
Clean the sides of the vessel while you were stirring.
Add the lemon juice just enough to curdle ,too much will give a lemon flavour.
Add sugar as per your taste.(I used very little and it was good).
After cooling I cut them into pieces which were very smooth.