Prepare Baking Dish:

Lightly grease a 9x13-inch baking dish. Place the croissant pieces evenly in the dish.

Make Custard Mixture:

In a large mixing bowl, whisk together the orange juice, orange zest, granulated sugar, eggs, whole milk, heavy cream, vanilla extract, ground cinnamon, and salt until well combined.

Combine and Soak:

Pour the custard mixture evenly over the croissant pieces in the baking dish. Press the croissants down gently to ensure they soak up the custard. Cover the dish with plastic wrap and refrigerate for at least 1 hour, or overnight for best results.

Preheat Oven:

Preheat your oven to 350°F (175°C).

Bake:

Remove the plastic wrap from the baking dish. Drizzle the melted butter over the top of the croissant mixture.

Bake in the preheated oven for 35-40 minutes, or until the top is golden brown and the custard is set.

Prepare Orange Glaze:

In a small bowl, whisk together the powdered sugar and 2 tablespoons of fresh orange juice until smooth. If the glaze is too thick, add a little more orange juice until you reach the desired consistency.

Serve:

Drizzle the orange glaze over the baked croissant breakfast bake.

Garnish with fresh orange slices and mint leaves if desired.

Serve warm.