Preheat the oven to 350°F.
Add the melted butter and sugar to a mixing bowl, mix until well combined.
Stir in the beer and the eggs, mix until well combined.
Stir in the melted chocolate.
Sprinkle with flour, salt, and coco powder, mix until just combined.
Toss the cherries with cornstarch. Stir into the batter.
Pour into a pan lined with parchment paper.
Bake for 40 minutes or until a toothpick in the center returns with a few crumbs attached but it’s covered in batter.
Allow to cool and rest for one hour before removing from the pan and cutting into squares