I give you the Krispy Kreme blueberry burger.
Start with a pint of blueberries, lightly mashed. Add enough sugar to coat, as well as a half teaspoon of powdered citric acid (or lemon juice) to give back a little brightness. Let sit for an hour. After an hour strain to separate the juice from the berries. Save both.
Whip up a half pint of heavy cream with powdered sugar and vanilla.
Take your donut and cut it in half around the equator, like a bagel. Then toast the cut side.
After it's toasted, take the bottom half and drizzle a bout 2 TB of the blueberry juice over the bottom half of the "bun". Top that with the whipped cream and enough berries to cover. Then just add the top of the "bun", more whipped cream and a few berries to decorate. Drizzle more of the juice over the whipped cream.
It's good. Trust me.