How to Make It
In a small saucepan, combine the sugar, honey and 1 cup of water and bring to a boil over low heat. cook until the syrup has reduced by half, about 10 minutes. Let cool.
Meanwhile, peel and core the apples and cut them into walnut-size pieces.
In a food processor, combine the apples, sugar syrup, Muscat, lemon juice and grappa and puree until creamy. Transfer the mixture to an ice cream maker and freeze until firm. Serve at once or transfer the sorbet to chilled containers and store in the freezer.