I prefer the Cherries pitted but not sliced.
The whole key to doing this is using high proof Bourbon.
Wild Turkey 101 or similar.
Pit cherries, Pack in jar, fill to the top with Bourbon and refrigerate. 2 week minimum but It then keeps in the fridge for at least a year. I mix cocktails and use the cherries as a garnish, they become little booze bombs. If you want it sweeter add simple syrup to the cocktail.