Make the cream cheese filling by placing softened cream cheese, powdered sugar, cream, and vanilla extract into a bowl and mix until smooth and well combined.
Cut brioche bread into 1 inch cubes.
Place some of your bread cubes into a greased baking dish in a single layer.
Add several spoonsful of cream cheese filling to the first layer.
Then add more brioche cubes and more cream cheese filling. Do this until you fill your baking dish.
Make the French toast custard by whisking together heavy cream, milk, eggs, vanilla, and cinnamon.
Pour the cream mixture over the brioche.
Next, cover the baking dish with plastic wrap.
Use your hands on top of the plastic wrap to press the bread cubes down into the custard.
Let the casserole sit, covered, for at least 1 hour before baking. You can leave it overnight in the refrigerator and bake the next morning.
Make the streusel topping by cutting chopped pecans, flour, brown sugar, and butter.
Preheat your oven to 350°.
Remove the plastic wrap from your casserole. Sprinkle streusel filling crisp cooked bacon pieces over the top evenly.
Cover the baking dish with aluminum foil and bake for 35 minutes.
After 35 minutes, remove the foil and bake for an additional 10 minutes. Use a toothpick or knife to check the center of the casserole for doneness. When the French toast bake is fully cooked, the custard in the bread cubes should be firm and hot.
Serve with maple syrup and a side of fresh cut fruit.