01 -
Set your oven to 350°F (175°C). Lay the croissant halves, cut side up, on a baking sheet lined with parchment. Toast them in the oven until they're nice and golden, about 10-12 minutes. Once cooled, break them into large pieces.
02 -
Scatter the torn croissants evenly in the base of a 9x13-inch dish.
03 -
Fry chopped bacon over medium heat in a pan until it's nice and crunchy. Use a slotted spoon to transfer the bacon to a paper towel-lined plate, saving 1 tablespoon of the bacon fat in the pan.
04 -
In the same pan with the leftover bacon fat, toss in the diced onion or shallot along with a dash of salt and pepper. Stir over medium heat for 3-5 minutes until softened and clear.
05 -
Spread cooked bacon, sautéed onions, and grated cheese on top of the croissants in the dish. Mix gently if you want to even things out.
06 -
Whisk together eggs, milk, cream, salt, and pepper in a medium-sized bowl. Make sure it's fully mixed, then pour this mixture evenly over the other ingredients in the dish.
07 -
Cover dish and place it in the fridge for at least 4 hours, max 12, so the flavors come together. Don't leave it too long or the croissants might fall apart.
08 -
Heat oven again to 350°F (175°C). Take the dish out of the fridge, uncover, and pop it on a baking tray with foil underneath to catch any spills. Bake for 45-50 minutes until it looks puffed up, golden, and solid when pressed lightly.
09 -
Let the dish rest for 10-15 minutes to settle before you serve.