In a bowl, mix the rolled oats with the milk and yogurt.
Chop the chocolate and fold it into the mix. Refrigerate.
Heat the cherries in a saucepan.
Remove 3 tablespoons of cherry juice and mix it with the cornstarch. Pour the mixture back into the sauce pan. Simmer for 2-3 minutes, until the mixture thickens. Sweeten with sugar or maple syrup and add cinnamon for spice.
In a glass, alternate layers of oats and cherries. Soak for at least 1 hour, or ideally, overnight.