Step 1 Place the peach pieces and one-half cup water in a saucepan over medium-high heat, cover and cook for about 5 minutes, until the peaches are tender and cooked through. Remove from the heat and stir in the sugar. Cool to room temperature.
Step 2 Add the orange liqueur and puree the mixture in a blender until smooth. Chill thoroughly, then freeze in your ice cream maker according to the manufacturer's instructions. This makes about one pint of sorbet.