Preheat oven to 350°F.
Cut brioche bread into 1 inch pieces. Place in a warm oven for about 8-10 minutes to dry slightly, or cut and let stand uncovered on the counter overnight.
Whisk together eggs, milk, cream, brown sugar and vanilla in a bowl.
Pour wet mixture over bread and very gently toss to coat. Place in a 8 x 8 inch baking dish. Allow to sit at least 1 hour (or overnight).
Combine topping ingredients and incorporate the butter using a fork or pastry blender until crumbly.
Cover the bread mixture with the topping and place in preheated oven for 30-35 minutes or until a knife inserted in the center comes out clean.
Serve warm with maple syrup, whipped cream or fruit.
(Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.)