Spread grapes onto a parchment-lined baking sheet in a single layer. Freeze for at least 4 hours, until fully frozen.

Add frozen grapes, agave, lemon juice, lemon zest, and salt to a food processor or high-speed blender. Blend until smooth and creamy, scraping down the sides as needed.

Serve immediately for a soft sorbet texture, or transfer to an airtight container and freeze for 1–2 hours for a firmer scoop.

Scoop into bowls and serve cold. Enjoy!