Put your frozen grapes in a food processor and pulse until the grapes have lost their shape. About 7-8 pulses.
Add in the sugar and lemon juice. Pulse until the the ingredients have created a smooth texture.
You can eat it just like that, or you can put it back in the fridge to let it get really cold again so you can get beautiful scoops of the sorbet using an ice cream scoop!
Store this in an airtight container for up to a month in the freezer. Enjoy!:)