Follow these easy steps to create the Overnight Croissant Breakfast:

1. Prepare Croissants: Slice the croissants in half horizontally. Arrange them in a greased 9×13-inch baking dish, cut-side up.
2. Mix Custard: In a large bowl, whisk together the eggs, milk, heavy cream, sugar, vanilla extract, cinnamon, and salt until well combined.
3. Combine: Pour the custard mixture evenly over the croissants, ensuring they are well soaked.
4. Add Berries: If desired, sprinkle mixed berries over the top of the croissants for added flavor and color.
5. Cover and Chill: Cover the baking dish with plastic wrap and refrigerate overnight.
6. Preheat Oven: In the morning, preheat your oven to 350°F (175°C).
7. Bake: Remove the plastic wrap and bake for 30-35 minutes, or until the custard is set and the tops are golden brown.
8. Cool Slightly: Allow the dish to cool for about 10 minutes before serving.
9. Dust with Sugar: Optionally, dust with powdered sugar for a sweet finish.

These steps will guide you in creating this incredible breakfast effortlessly.