Preheat the oven to 375 degrees F. Butter a 1 1/2 quart baking dish.Place the cherries in the bottom of the baking dish.Put all remaining ingredients (except for the powdered sugar) in a blender and blend until smooth. Pour the batter over the cherries, place the baking dish on the middle oven rack, and bake for 30-40 minutes until the top is a rich golden brown, the clafoutis is set but still slightly jiggly. Remove it from the oven and let it cool for 5-10 minutes before serving. Sprinkle with powdered sugar. Serve warm with whipped cream or vanilla custard.