Ingredients

• 1/3 cup almond paste (3 1/2 ounces; preferably Caffè Sicilia brand)
• 2 tablespoons sugar
• 2 cups bottled spring water (not carbonated)
• Accompaniments: warm brioche; espresso

Instructions

1. Blend together almond paste, sugar, and 1 1/2 cups water in a blender until smooth, foamy, and white. Pour through a fine-mesh sieve into an 8-inch square baking pan, reserving any solids in sieve. Add remaining 1/2 cup water to solids in sieve and whisk over baking pan until most of water passes through (do not press on solids).
2. Stir mixture, then freeze, stirring and crushing lumps with a fork every 30 minutes, until firm but not frozen hard, 2 to 3 hours. Scrape with a fork to lighten texture, crushing any lumps.