Bring all ingredients to a boil in a large heavy saucepan; reduce heat to medium-low. Simmer until cherries are softened and start to release juices, about 10 minutes. Using a slotted spoon, transfer cherries to a medium heatproof bowl.
Simmer juices until thick enough to coat the back of a spoon, 15–20 minutes. Pour reduced syrup over cherries. Serve warm.
