From Mastering The Art of French Cooking
2 to 3 cups cherries
1 1/4 cups milk
1/3 cup sugar
1 tablespoon vanilla
hearty pinch of salt
1/2 cup flour
Preheat oven to 350 degrees. Butter up your pan.
Pit the cherries, and set aside. Whisk all ingredients together in a medium bowl until combined. Pour a thin layer of batter into the pan until the bottom is just coated. Place the pan in the oven for 5 minutes, or until the film of batter has set. Remove from the oven, and arrange the cherries in the pan. Pour the remaining batter carefully over the cherries, and bake for at least an hour. It may takea bit longer, but it will be done when a tester comes out clean, and it is puffed and browned. Sprinkle with powdered sugar.
Note: It is très more French to leave the pits in, but I spent too much for a cherry pitter three years ago, and jump on every opportunity to actually have a reason to bust it out.