Preheat oven to 375º. Grease a 12 × 14 baking dish. Cut bread into 1 slices and lay flat in pan. Brush tops of bread with melted butter. Whisk together eggs, milk, cream, sugar and vanilla. Pour over bread and let sit 15 minutes. Place dish in water bath and bake for 35 minutes. Serve with warmed blackberries and whipped cream.