Spray a 9x13-inch (23x33 cm) baking dish with nonstick cooking spray and set aside.

Make the almond cream by combining the almond flour, softened butter, sugar, almond extract, and beaten eggs in the bowl of a stand mixer. Mix until smooth. Scrape down the bowl, add the flour, and mix again. Set aside.

Preheat the oven to 350°F (177°C).

Make the bread pudding base. Whisk the beaten eggs, milk, heavy cream, melted butter, granulated sugar, brown sugar, cinnamon, vanilla extract, almond extract, and nutmeg in a large mixing bowl until the custard mixture is completely blended.

Tear the bread into rough 2-inch (5 cm) pieces and spread half of it in the prepared baking dish.

Pour half of the custard mixture over the bread so it fully absorbs into the pieces.

Transfer the almond cream to a large pastry bag and cut a 1-inch (2.5 cm) opening. Pipe dollops of almond cream evenly over the soaked bread layer.

Add the remaining bread to the dish and pour the rest of the custard mixture evenly over the top.

Scatter the sliced almonds over the surface, pressing a few lightly into the bread so they adhere during baking.

Let the mixture rest for at least 10 minutes.

Cover the dish loosely with tented foil and bake for 45 to 50 minutes, removing the foil during the last 5 minutes.

Make the brown sugar glaze by melting the butter in a small saucepan over medium heat. Add the brown sugar and whisk until dissolved and lightly foamy. Whisk in the vanilla, then the heavy cream, until the sauce becomes smooth. Remove from the heat.

Pour the warm glaze evenly over the baked bread pudding. Serve warm.