Prepare the cherries by rinsing, de-stemming, halving, and pitting them.

Use a blender or food processor to purée the cherries.

Reduce the purée in a small saucepan over medium heat.

Stir frequently and cook it down until you have just a few tablespoons of jammy reduction remaining. It took me about 15 minutes. Be very careful to not let it burn. Remove the reduction from the pan and allow it to cool.

Whip the butter and half of the powdered sugar together for 5 minutes in a stand mixer with a paddle attachment. This is to get the perfect fluffy texture and structure in the frosting. 

Add in the vanilla and half of the cherry reduction. Mix until just blended. Add the remaining half of the powdered sugar and mix. Finally, add remaining reduction and salt and mix to combine.