Step 1

Combine cherries, syrup and vanilla bean in a large pan over medium heat. Cook, stirring occasionally, until cherries are very soft and beginning to break down, 20 to 25 minutes. Remove pan from heat. Remove and discard vanilla bean. Roughly mash cherries with a potato masher; let mixture cool completely, about 1 hour.

Step 2

Stir together buttermilk, sugar and salt in a large bowl, whisking until sugar dissolves. Add cherry mixture and stir to combine. Pour mixture into a 2-quart electric ice cream maker and freeze according to manufacturer's instructions. Transfer ice cream to a freezer-safe container; cover and freeze until firm, about 2 hours.