I created this Festive Holiday Breakfast Casserole because Christmas morning in our house was always beautiful chaos—wrapping paper mountains, twinkling lights, three excited kids, and a rumble of hungry tummies by 9 a.m. My mother-in-law would arrive with her famous cinnamon rolls, but we still needed something savory, hearty, and—most importantly—hands-off so I could sip coffee while the kids tore into gifts. After years of tweaking (and more than a few dry edges), this sausage-and-cheese version emerged as the clear winner. Cubes of crusty sourdough soak up a mustard-kissed custard, breakfast sausage perfumes every bite, and a blanket of melty cheddar plus a pop of roasted red pepper makes the whole dish feel special-occasion worthy. Now I prep it every Christmas Eve, stash it in the fridge, and slide it into the oven while "Santa" is still arranging presents under the tree. When the last bow is untied, we gather around the table, still in pajamas, and scoop out steaming squares of comfort. It tastes like tradition, smells like the holidays, and—best of all—lets the cook enjoy the morning, too.

Ingredient Breakdown

Great casseroles start with intentional ingredients. Here's why each matters:

• Sourdough or French Bread—stale is best. Dry cubes act like little sponges, soaking up the custard without turning to mush. If your loaf is fresh, cube it and let it sit uncovered overnight.
• Breakfast sausage. I use mild pork for universal appeal, but sage or maple links add extra flair. Remove casings and crumble so every bite is seasoned.
• Sharp cheddar + a handful of Gruyère. Cheddar brings classic flavor; Gruyère adds nutty sophistication and that Instagram-worthy cheese pull.
• Eggs + half-and-half. The 1:1 ratio creates a custard that's rich yet sliceable. Swap with whole milk for a lighter version, but expect a slightly looser texture.
• Dijon + Worcestershire. These umami bombs brighten the heavy ingredients—don't skip!
• Roasted red peppers + green onions. Little pops of color signal "celebration" and balance the richness.

Step-by-Step Instructions

1. Prep your pan & oven. Butter a 9×13-inch baking dish (glass or ceramic) and set on a foil-lined rimmed sheet to catch any drips. Pre-heat oven to 350 °F/175 °C.
2. Toast the bread (optional but recommended). Spread cubes on a sheet pan; bake 8 minutes until edges feel dry. Cool while you cook the sausage.
3. Brown the sausage. In a large skillet over medium heat, crumble sausage, cooking until no pink remains, 6–7 minutes. Transfer to paper-towel-lined plate; discard drippings, reserving 1 tsp for veggies.
4. Sauté the aromatics. In same skillet, melt butter with reserved drippings. Add diced onion and bell pepper; cook 4 minutes until translucent. Stir in minced garlic for 30 seconds; remove from heat.
5. Build the base. Scatter half of the toasted bread cubes into prepared dish. Top with half of sausage, half of sautéed veggies, half of roasted red pepper strips, and half of both cheeses. Repeat layers, ending with cheese.
6. Whisk the custard. In a large bowl whisk eggs, half-and-half, Dijon, Worcestershire, salt, pepper, and nutmeg until homogenous. Pour evenly over casserole, pressing lightly so every cube is moistened.
7. Refrigerate overnight (or at least 30 minutes). Cover with buttered foil; chill to let bread fully absorb custard. If you're short on time, 30 minutes at room temp works in a pinch.
8. Bake. Remove from fridge 30 minutes prior. Bake covered 30 minutes, then uncover and bake 25–30 minutes more, until center puffs and a thermometer reads 180 °F/82 °C. Broil 1–2 minutes for bronzed cheese.
9. Rest & garnish. Let stand 10 minutes to set custard. Sprinkle with sliced green onions and a dusting of smoked paprika for festive color.
10. Serve. Cut into 12 squares; serve hot with fresh fruit, cranberry mimosas, and holiday cheer.

Expert Tips & Tricks

• Cube bread uniformly. ¾-inch pieces ensure even custard absorption; use a serrated knife for tidy edges.
• Under-season the sausage, over-season the custard. Sausage salt varies; taste your egg mixture—it should be slightly saltier than you want because bread tempers it.
• Layer, don't mix. Distinct strata keep cheese from sinking to the bottom and create melty pockets throughout.
• Use room-tempo dairy. Cold half-and-half can seize melted butter; let it sit out 15 minutes while you sauté.
• Test doneness with jiggle. Center should spring back gently and have only a slight wobble; residual heat finishes cooking while it rests.
• Make mini versions. Divide among greased muffin tins; bake 20–22 minutes for portable holiday brunch bites.

Common Mistakes & Troubleshooting

Variations & Substitutions

• Vegetarian: Swap sausage for 1 lb cremini mushrooms sautéed with smoked paprika & fennel seed.
• Tex-Mex: Use chorizo, pepper-jack, diced green chiles, and a scoop of salsa on top.
• Lightened-up: Turkey sausage, 1% milk, reduce cheese by ⅓; add spinach for bulk.
• Gluten-Free: Sub cubed GF cornbread; reduce liquid by ¼ cup (cornbread is softer).
• Dairy-Free: Use coconut milk (full-fat) and vegan cheddar shreds; add 1 tsp nutritional yeast for nuttiness.
• Holiday Luxe: Fold in ½ cup chopped smoked salmon and swap Gruyère for brie (cube, freeze 15 min before layering).

Storage & Freezing

Refrigerate: Cool completely, cover tightly, and refrigerate up to 4 days. Reheat squares in microwave 60–90 seconds or in a 325 °F oven for 15 minutes.

Freeze: Cool, slice, wrap individual squares in plastic + foil, and freeze up to 2 months. Thaw overnight in fridge, then reheat as above.

Make-ahead raw: Assemble through Step 7, wrap twice, and freeze up to 1 month. Thaw 24 hours in fridge, bring to room temp 1 hour, then bake as directed.

Frequently Asked Questions

Happy holidays and happy brunching! May your morning be merry, your coffee strong, and your casserole golden.

Festive Holiday Breakfast Casserole

4.7

Print Recipe Pin Recipe

A make-ahead sausage and cheese bake perfect for holiday mornings with family.

Prep

20 min

Cook

45 min

Total

1 hr 5 min

Serves 12

Easy

Ingredients

• 1 lb breakfast sausage
• 6 slices white bread, cubed
• 2 cups shredded cheddar
• 1 cup shredded mozzarella
• 8 large eggs
• 2 cups whole milk
• 1 tsp dry mustard
• ½ tsp salt
• ¼ tsp black pepper
• ¼ tsp paprika
• 1 small red bell pepper, diced
• 3 green onions, sliced
• ¼ cup grated parmesan
• Butter for greasing
• Fresh parsley for garnish

Instructions

1. 1
   Brown sausage in a skillet over medium heat until fully cooked; drain and set aside.
2. 2
   Grease a 9×13-inch baking dish with butter and spread cubed bread evenly on the bottom.
3. 3
   Layer cooked sausage, bell pepper, and green onions over the bread.
4. 4
   In a bowl, whisk eggs, milk, mustard, salt, pepper, and paprika until smooth.
5. 5
   Sprinkle cheddar and mozzarella evenly over the casserole, then pour egg mixture on top.
6. 6
   Cover and refrigerate at least 2 hours or overnight for best flavor.
7. 7
   Preheat oven to 350 °F (175 °C). Let dish sit at room temp 15 min before baking.
8. 8
   Bake uncovered 40–45 min until golden and center is set; top with parmesan last 5 min.
9. 9
   Cool 10 min, garnish with parsley, slice, and serve warm.

Recipe Notes

• Assemble the night before for stress-free mornings.
• Swap in turkey sausage or add spinach for a lighter twist.
• Leftovers reheat well in the microwave for up to 3 days.

Nutrition (per serving)

Calories

385

Protein

22 g

Carbs

14 g

Fat

27 g