Smooth and refreshing, this sweet-tart sherbet is the perfect finale for a summer meal. Although kiwis contain an enzyme that curdles milk, in this recipe the use of heat and buttermilk avoids that potential problem.
Place the kiwis, sugar, and lime juice in a food processor and purée. The kiwi mixture can be slightly chunky. If you don't want seeds to speckle the sherbet, place the mixture in a fine mesh sieve and strain, pressing hard on the solids.
Transfer the purée to a small pan and bring just to the start of a simmer over low heat, stirring frequently. Remove from the heat, transfer to a container with a lid, and add the buttermilk and corn syrup, stirring to blend. Cool completely in the refrigerator, at least 2 hours.
When cold, pour the mixture to an ice cream maker and process according to the manufacturer's instructions. When the sherbet begins to set up, add the cream to the ice cream machine and run another 5 to 10 minutes. Transfer the sherbet to a clean container, cover, and freeze until solid.