Wash the peaches thoroughly if using fresh. Slice each peach into 8 segments and peel each slice.

Add the peach slices and caster sugar into the bowl of a food processor. Blend until smooth, stopping to scrape down the sides as needed.

Once fully blended, add lemon juice. Start with 1 tablespoon, then blend and taste. Adjust the amount of lemon juice to your preference.

Pour the mixture into a freezer-safe container and smooth the surface.

Cover the container tightly with a lid or plastic wrap.

Freeze for 6 to 7 hours, or until firm.

Before serving, let the sorbet sit at room temperature for 5–10 minutes to soften slightly. Scoop and serve immediately.