Start by rolling the lemons firmly on the counter to loosen the juice, then cut them in half and juice until you have about 1 cup of fresh lemon juice, catching any seeds with a fork or strainer.
Finely grate a teaspoon of lemon zest using a microplane or fine grater, avoiding the bitter pith, and set aside.
In a mixing bowl, combine the lemon juice, sugar, water, lemon zest, and a tiny pinch of salt, stirring vigorously until the sugar dissolves completely and the mixture is smooth and bright.
Pour the mixture into a freezer-safe container, cover it tightly, and place it in the freezer.
Every 30 minutes, remove the container from the freezer and scrape the mixture vigorously with a fork to break up ice crystals and promote a granular texture.
Repeat this scraping process for about 4 hours or until the sorbet feels firm yet scoopable, with a crackly, icy surface.
Serve the lemonade sorbet in bowls, garnished with fresh herbs if desired, for a crisp, icy burst of citrus flavor that shatters with each spoonful.
