Adjust oven rack for baking on middle rack. Preheat oven to 350°F.
With a bread knife, cube the French bread into 1 1/2 inch cubes. Place in large bowl and set aside.
Remove frozen berries from freezer to defrost while preparing the rest of the ingredients.
In a small bowl, combine the 4 Tablespoons melted butter and 1/2 cup brown sugar. Spread mixture inside the bottom of a large cast iron pan (5-7 quart). This will create a yummy caramelization on the bottom of the French Toast Bake!
In a medium bowl, whisk together the beaten eggs, milk, vanilla and 1 Tablespoon cinnamon. Pour evenly over the cubed bread, slightly tossing to coat all of the bread.
Pour coated bread into the cast iron pan over the brown sugar mixture and spread it out evenly. Bake uncovered for 25 minutes. (If bread starts to brown too much, cover with lid.)
While bread is baking, prepare the Topping. In a small bowl, combine all Topping ingredients and set aside.
After the bread has baked for 30 minutes, remove from oven. Sprinkle the berries on top of the bread. Sprinkle the topping evenly over the berries. Return to oven and bake, uncovered, an additional 30 minutes. (If topping or fruit starts to brown, place lid on pan.)
Remove from oven, place lid on pan and let sit for 5 minutes before serving.
Best served warm! (Tastes so yummy with whipped cream!)