Grease a 9"x13" casserole dish with either vegetable oil or butter to prevent sticking. Cut the French bread into cubes, then add enough cubes to the casserole dish to fill it about three-quarters full. This creates the base for the baked French toast.

In a large bowl, whisk together the eggs, 2% milk, vanilla extract, ground cinnamon, and packed light brown sugar until well combined and the sugar is dissolved. This will be the custard that soaks into the bread.

Pour the custard mixture from Step 2 evenly over the cubed bread in the casserole dish, making sure all the bread is moistened. Slice the strawberries, then scatter the sliced strawberries and blueberries over the top of the bread. This adds a fresh and colorful layer of fruit.

Wrap the assembled casserole tightly with saran wrap, then refrigerate it for at least four hours, or overnight. Chilling allows the bread to soak up the custard mixture fully, resulting in a creamier texture. I find letting it sit overnight gives the best flavor and consistency.

Preheat your oven to 350°F (175°C). Remove the casserole from the refrigerator and bake uncovered for 35 to 50 minutes. Check at the 35-minute mark; the dish should be set in the center and golden on top. If not, continue baking until done.

Once baked, remove the casserole from the oven and let it cool slightly. Sprinkle confectioners' sugar generously over the top for a beautiful finish. Serve with maple syrup for the perfect sweet touch. I always let my casserole rest for 5 minutes before slicing—this helps the pieces hold together when served.