Ingredients:
- 1 kg large butter croissants, torn into 2-inch chunks
- 450g pork breakfast sausage, bulk
- 1 large leek, white and light green parts only, thinly sliced
- 12 large eggs, room temperature
- 950ml whole milk
- 240ml heavy cream
- 15g Dijon mustard
- 5g kosher salt
- 3g freshly cracked black pepper
- 2g freshly grated nutmeg
- 340g sharp Gruyère cheese, coarsely grated
- 30g fresh chives, finely minced
- 1 pinch red pepper flakes
Instructions:
- Preheat to 375°F (190°C) and grease a large 9x13 inch baking dish.
- Cook 450g pork sausage in a skillet over medium heat until browned and crumbly. Drain the excess fat.
- Add the sliced leeks to the same skillet and cook until translucent and fragrant.
- Break 1 kg of croissants into 2 inch pieces and spread them in the prepared baking dish.
- Combine 12 eggs, 950ml milk, 240ml cream, 15g Dijon, salt, pepper, and 2g nutmeg. Whisk until no streaks of yolk remain.
- Sprinkle the cooked sausage, leeks, and 340g Gruyère over the croissant chunks.
- Pour the egg mixture over the croissants. Press down with a spatula so every piece is submerged.
- Let the dish sit for 20 minutes (or up to 12 hours) until the croissants feel heavy and saturated.
- Bake in the preheated oven for 45 to 50 minutes until the center is set and the top is golden brown.
- Sprinkle with chives and red pepper flakes. Wait 10 minutes before slicing to let the custard stabilize.