Cube and Arrange the Bread: Grease a 9x13-inch ceramic or glass baking dish generously with softened butter. Spread the cubed brioche bread evenly across the prepared dish, gently pressing them into an even, layered base.

Whisk the Custard Mixture: In a large mixing bowl, whisk together the 8 eggs, whole milk, heavy whipping cream, maple syrup, vanilla extract, ground cinnamon, nutmeg, and salt until completely smooth, frothy, and thoroughly emulsified.

Soak the Bread: Pour the custard slowly and evenly over all the bread cubes, making sure every corner is saturated. Use the back of a large spoon or spatula to gently press down on the cubes so they absorb the liquid. Cover tightly with plastic wrap and refrigerate overnight (or for at least 4 hours).

Prepare the Pecan Praline Topping: In the morning, preheat your oven to 350°F (175°C). In a medium bowl, stir together the melted butter, dark brown sugar, chopped pecans, maple syrup, ground cinnamon, and pinch of sea salt until a thick, crumbly, glossy paste forms.

Spread & Bake to Perfection: Uncover the casserole dish and drop dollops of the pecan praline mixture evenly over the soaked bread, spreading it gently with a spoon across the top surface. Bake uncovered for 40 to 45 minutes, until the casserole is puffed, the center is gently set, and the pecan praline topping is deeply golden-brown and bubbling.

Rest, Dust, and Serve: Allow the bake to rest for 10 minutes to settle into neat slices. Dust generously with powdered sugar and serve warm with a generous drizzle of warm pure maple syrup and fresh berries!