On very low heat, add the sesame seeds and roast in a pan for 3-5 minutes. Remove from heat as soon as it is slightly fragrant and a light golden color. Transfer to a plate immediately to stop them from roasting further.
In the same or different pan over low heat, add the jaggery and a couple of tablespoons of water.
If using whole jaggery, make sure it is broken into similar-sized pieces.
Let it cook on low heat. Once it starts to bubble, add a small drop of melted jaggery into a bowl of water. If it forms into a ball, it is ready.
If it spreads in the water, cook for a few minutes.
Now add the sesame seeds and turn off the heat. Mix until all the sesame seeds are coated with jaggery.
Let the mixture cool slightly (5-10 minutes).
Use a small spoon or a small melon scoop to portion the mixture. Take one portion of the mixture and roll it into a ball.
If the sesame seeds are sticking to your hand, oil your hands slightly before handling the mixture.
Once all the ladoos are shaped, let them cool completely.
Store at room temperature in an airtight container for 2-3 weeks.