Description
Buttery croissants soak up a creamy egg custard with smoky ham, nutty Gruyere, and fresh herbs. It bakes up golden and crisp on top with a soft, custardy center that’s perfect for brunch.
Ingredients
10 large croissants
6 oz sliced ham
2 cups shredded gruyere cheese
4 tablespoons unsalted butter
1 yellow onion, diced
1 tablespoon minced fresh thyme
2 tablespoons minced fresh sage
2 1/2 cups half and half
6 eggs
1 tablespoon dijon mustard
1 tablespoon whole grain mustard
1 1/2 teaspoons kosher salt
1/2 teaspoon ground black pepper
1/8 teaspoon freshly grated nutmeg
Minced chives, for garnish
Optional: Hollandaise sauce for serving
Instructions
1. Tear croissants into pieces and let them sit overnight to stale, or bake at 250°F for 40 minutes to dry out.
2. Melt butter in a skillet over medium heat. Sauté onions for 2–3 minutes, then add sage and thyme. Cook another 2–3 minutes until soft.
3. Grease a 9×13 baking pan.
4. Layer half the croissants in the pan, then add half the ham, half the cheese, and all the sautéed onions. Repeat with remaining croissants, ham, and cheese.
5. Whisk together eggs, half and half, dijon, whole grain mustard, nutmeg, salt, and pepper until smooth.
6. Pour custard over the casserole, gently press croissants down to soak, and let sit for 30 minutes.
7. Preheat oven to 350°F.
8. Bake for 40–45 minutes until puffed and golden brown. Check at 30 minutes; cover with foil if browning too quickly.
9. Cool for 5–10 minutes, garnish with chives, and serve.
Notes
Do not use fresh croissants; stale ones absorb the custard better without getting soggy.
Use freshly grated cheese for best texture and melting.
Avoid pre-soaking the casserole overnight as it may become too wet.
High-quality deli ham, such as French or uncured smoked, is recommended.
Custard and dry components can be prepared separately the night before and assembled in the morning.
Storage: Refrigerate leftovers for up to 3 days, tightly wrapped; reheat at 350°F for 15–20 minutes.
Freezing: Wrap cooled casserole in plastic wrap and freeze in a ziplock bag for up to 2 months. Thaw in refrigerator before reheating.
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Category: Breakfast Recipes
- Method: Baked
- Cuisine: American
Nutrition
- Serving Size: 1 piece
- Calories: 684
- Sugar: 12 g
- Sodium: 1333 mg
- Fat: 47 g
- Saturated Fat: 26 g
- Unsaturated Fat: 17 g
- Trans Fat: 0.2 g
- Carbohydrates: 38 g
- Fiber: 2 g
- Protein: 27 g
- Cholesterol: 261 mg