Overnight Cheesy Breakfast Casserole

This hearty Overnight Cheesy Sausage and Hashbrown Breakfast Casserole has saved countless weekend morning rushes in my home. Prepping it the night before means waking up to the promise of a hot, comforting breakfast without the early morning kitchen chaos.

I first created this casserole when my inlaws surprised us with an overnight visit. The next morning, everyone raved about it while I secretly smiled knowing I had barely lifted a finger that morning.

Ingredients

• Shredded mild cheddar creates that perfect golden, bubbly top and adds rich flavor throughout
• Frozen shredded hash browns serve as the hearty base no need to thaw them first
• Breakfast sausage brings protein and savory depth choose hot variety for extra kick
• Milk creates the perfect custard texture when combined with eggs
• Eggs bind everything together while adding protein and richness
• Onion powder infuses flavor without the texture of chopped onions perfect for picky eaters
• Garlic powder adds subtle depth that complements both the sausage and potatoes
• Salt and pepper ensure every bite is properly seasoned

Step-by-Step Instructions

Prepare The Sausage

Cook sausage in a large frying pan until completely browned, breaking it into crumbles as it cooks. This usually takes about 7-9 minutes over medium heat. Drain thoroughly on paper towels to remove excess grease which prevents a soggy casserole.

Brown The Hash Browns

Using the same pan with a bit of the sausage flavor, lightly brown the hash browns until they just begin to crisp on the edges about 5-7 minutes. This step creates texture and prevents the potatoes from becoming mushy during baking. Work in batches if needed to ensure even browning.

Layer The Casserole

Arrange the lightly browned hash browns as the bottom layer in your greased 9x13 dish, pressing gently to create an even base. Sprinkle the cooked sausage evenly over the potatoes, then distribute the shredded cheese across the top, ensuring complete coverage.

Create The Egg Mixture

Whisk the eggs until well beaten, then slowly incorporate the milk while continuing to whisk. Add all the seasonings and whisk until everything is fully incorporated. The mixture should have a consistent color with no streaks of egg white remaining.

Assemble And Refrigerate

Pour the egg mixture slowly and evenly over the entire casserole, allowing it to seep down between the layers. Cover tightly with aluminum foil and refrigerate overnight, which allows the flavors to meld and the egg mixture to penetrate all ingredients.

Bake To Perfection

Remove the casserole from the refrigerator while your oven preheats to 350°F. Bake uncovered for exactly 40 minutes the top should be golden brown and slightly puffy, with cheese bubbling around the edges. Let rest for 5 minutes before serving to set completely.

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The breakfast sausage is truly the heart of this recipe. I discovered this after trying it with bacon once and while delicious, the sausage version always disappears faster at our family gatherings. Something about how the spices in the sausage infuse the entire casserole makes it irresistible.

Make It Your Own

This casserole welcomes customization based on what your family enjoys. Try adding sautéed bell peppers and onions for extra vegetables, swap the cheddar for pepper jack if you prefer a spicier profile, or mix in some cooked, crumbled bacon alongside the sausage for an extra indulgent version. My teenage son loves when I add a layer of sautéed mushrooms, while my daughter prefers extra cheese on her portion.

Storage And Reheating

Once baked and cooled, this casserole can be refrigerated for up to 3 days. Cut into individual portions before storing to make reheating quicker. Microwave individual servings for 60-90 seconds or reheat larger portions covered with foil in a 325°F oven for about 15 minutes until warmed through. The texture remains surprisingly good even after reheating, unlike many egg dishes that can become rubbery.

Serving Suggestions

While this casserole is essentially a complete meal on its own, I love serving it with a light fruit salad to balance the richness. A simple mix of berries, orange segments and mint makes the perfect side. For special occasions, offer small glasses of mimosas or a build your own Bloody Mary bar to create a festive brunch atmosphere. Set out some warm maple syrup on the side too some guests enjoy drizzling a little over their portion for a sweet and savory combination.

Holiday Tradition

This casserole has become our Christmas morning tradition. I assemble it after the kids go to bed on Christmas Eve, and while they're opening presents the next morning, this casserole bakes to perfection. The wonderful aroma fills the house, and we can enjoy a special breakfast without anyone missing the holiday excitement. Every year, my family actually reminds me the week before Christmas not to forget "the casserole," as if I could ever forget our most requested breakfast tradition.

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Recipe FAQs

→ Can I make this casserole without refrigerating overnight?

Yes! While refrigerating overnight allows the flavors to meld and saves morning prep time, you can assemble and bake it immediately. Just follow all the preparation steps and bake in a 350°F oven for 40 minutes or until the cheese is bubbly and golden brown.

→ Can I use turkey sausage instead of regular breakfast sausage?

Absolutely! Turkey sausage works as a lighter alternative. The flavor profile will be slightly different but still delicious. Make sure to fully cook the turkey sausage before adding it to the casserole.

→ How long can I keep the unbaked casserole in the refrigerator?

The assembled unbaked casserole can be refrigerated for up to 2 days before baking. Just make sure to keep it tightly covered with foil or plastic wrap to prevent it from absorbing other flavors in your refrigerator.

→ Can I freeze this breakfast casserole?

Yes, this casserole freezes well both before and after baking. To freeze unbaked, assemble completely, cover tightly, and freeze for up to 3 months. Thaw overnight in the refrigerator before baking. For baked leftovers, cool completely, portion, and freeze in airtight containers for up to 2 months. Reheat individual portions in the microwave.

→ What can I serve with this breakfast casserole?

This hearty casserole pairs well with fresh fruit, yogurt, toast or biscuits, and a simple green salad for brunch. For a complete breakfast spread, consider adding some pastries or muffins and a variety of juices or coffee.

→ Can I add vegetables to this casserole?

Definitely! Sautéed bell peppers, onions, spinach, or mushrooms make excellent additions. Cook vegetables until soft and moisture is released before adding them to the casserole to prevent excess liquid during baking.