Method:-
Making chenna for rasgulla

On medium heat boil milk and bring it to boil. Add 1/4 cup of water with lemon juice and add to the boil milk until the milk curdles. Once the milk is curdled completely, switch off the gas and let it rest for 2 mins. Add cold water to the pot to prevent from cooking further.

Place a colander over a large bowl and line it with a thin muslin cloth. Drain the curdled milk. Rinse the chenna under running water to remove the acidic flavour. Squeeze it well to remove excess whey as much as possible. Leave it for about an 1 hour. Chenna should not have any excess whey and must be crumbly.

Making sugar syrup
Add sugar and water in a wide pan and bring it to a boil. Add rose water to the syrup.

Making rasgulla
Knead the chenna well to make it a smooth dough for about 3 minutes until the mixture turns uniformly smooth and is not grainy. Add colour if preferred. Make small balls from chenna. The balls will double in size so ensure they are half the size you would like your rasgulla to be. On medium flame bring the sugar syrup to boil and add the balls very gently.

Cover the pot with a lid. Cook on a medium flame for 9 to 10 mins. Keep the lid closed otherwise they will shrink or fall flat. Do not open at least for 20 mins.
Allow rasgulla to cool completely. Serve them chilled. If desired garnish with saffron.

You can also set aside some chenna and add icing sugar to it and pipe on top of the rasgulla and serve.