Stir in lemon juice and zest. Pour lemon syrup into a square metal cake pan and place in freezer. Freeze 2 hours in all, removing pan from freezer every 30 minutes, stirring and scraping with a metal fork until ice crystals break up. After 2 hours, granita will resemble snow.
Directions In a small saucepan, bring water and sugar to a boil. Cook and stir until sugar is dissolved. Remove thyme sprigs. Freeze for 1 hour; stir with a fork. Stir granita with a fork just before serving; spoon into dessert dishes. Garnish with lemon zest.
Optional: grate some lemon zest over the top. Or transfer your granita to a freezer-safe container & store in the freezer. Note: the only macros in this recipe come from the 1.5 cups of fresh lemon juice. Remove the granita from the freezer at least 15 minutes before serving to soften slightly.
With almost no calories and less than 5 grams of carbs, it's totally guilt-free and ideal for the keto diet. There are many different varieties of lemon you can use to make this low-carb granita.