Preheat oven to 375 degrees F. Poach the oysters in their own liquid for one minute, just until their edges begin to curl. Strain the oysters out of the liquid and set aside. Add enough water to the poaching liquor to bring it to 2 cups. Set aside. Melt butter in a saucepan over medium-high heat and add onions, celery, bell peppers, green onions and garlic. Sauté 3 to 5 minutes or until vegetables are wilted. Add flour and cook for 2 minutes. Deglaze with Chardonnay, whipping cream and the oyster liquid. Using wire whisk, blend well. Season with salt and pepper. Simmer for a few minutes until the sauce thickens. Fold in the cheese and sprinkle in bread crumbs. Set aside to cool. Arrange the oysters in individual ovenproof dishes (6 per portion) and cover with the Bienville sauce. Bake for 15 minutes, or until the sauce begins to brown on top.