Sausage Croissant Breakfast Casserole

Waking up to the smell of buttery croissants, savory sausage, and bubbling cheese is a luxury that makes any morning feel like a special occasion — whether it’s Christmas, Mother’s Day, or just an indulgent lazy Sunday. This sausage croissant breakfast casserole transforms day-old croissants into something flaky, rich, and comforting. It’s like a breakfast sandwich turned into a bake.

Unlike traditional breakfast casseroles made with cubes of plain bread, this one uses torn croissants that soak up the creamy custard without losing their buttery texture. The result? Golden, crispy edges with a soft, custardy center, punctuated by savory sausage, aromatic sage, and nutty Gruyère cheese. Best of all, it can be prepped the night before, so all you have to do in the morning is pop it in the oven and pour yourself a cup of coffee before everyone else wakes up.

• You can assemble it the night before for a no-fuss morning. It only takes 10 minutes of prep, so it’s not going to take too long to whip up.
• It’s got a great custardy texture. The mix of whole eggs and yolks makes it extra creamy. Plus, the torn croissants give the casserole an indulgent twist.

• Eggs: A combination of whole eggs and yolks creates a rich, silky custard when combined with milk and heavy cream.
• Fresh herbs: Finely chopped sage infuses the casserole with an earthy, herbaceous aroma, while a scallion garnish cuts through the richness and brightens the dish.
• Day-old croissants: Their buttery layers absorb the custard beautifully without becoming mushy. Large croissants have more exaggerated pockets for holding the custard, but mini croissants work here, too.
• Pork breakfast sausage: Buying loose sausage is easiest; otherwise, you need to remove the casing from links. You can also try flavored sausages, such as sage breakfast sausage and maple breakfast sausage. Even mild Italian sausage works in a pinch.
• Gruyère cheese: Melts into gooey pockets with a slightly nutty, sweet flavor that complements the croissant and sausage. Monterey Jack or mild white cheddar can be used as a substitute.

1. Make the custard. Mix the custard by whisking together eggs, egg yolks, milk, cream, sage, salt, and pepper. Stir in roughly torn croissants and let them absorb the custard.
2. Cook the sausage. While the croissants soak, cook the sausage on the stovetop.
3. Stir in the sausage. Add the cooked sausage to the custard. Stir to combine, which helps distribute the ingredients more evenly than layering them in the baking dish.
4. Bake the casserole. Pour the mixture into the dish, sprinkle with the cheese, and bake until golden-brown.