Sausage Potato Breakfast Casserole with Egg Custard
Layered breakfast casserole with dried brioche cubes, ground pork sausage, sliced potatoes, mushrooms, and spinach bound together with an egg custard made from eggs, milk, and half-and-half. Baked until the potatoes are tender and topped with melted cheese.
Ingredients
- 6 ounces bread cubed, brioche
- 1 pound ground pork
- 2 cloves garlic, minced
- 1 large yellow onion, diced
- 1 teaspoon ground sage
- 1 teaspoon fresh thyme leaves
- 1 teaspoon light brown sugar
- 1 pinch red pepper flakes
- 8 ounces cremini mushrooms, sliced
- 1 pound spinach, cooked
- 2 pounds Yukon gold potatoes, sliced thinly
- 8 ounces shredded cheese, Colby jack
- 6 large eggs
- 1 cup milk
- 1 cup half and half
- ½ teaspoon ground nutmeg
- 1 teaspoon salt
- ½ teaspoon black pepper
Instructions
- 1
Spread cubed bread on a baking sheet in a single layer and dry in a low oven for 20 minutes, tossing halfway through, until dried out but not browned.
- 2
Spray a casserole dish with non-stick spray or butter it. Place dried bread in the bottom.
- 3
Whisk together eggs, milk, half-and-half, nutmeg, salt, and pepper. Pour half the mixture over the bread and lightly press down to cover.
- 4
Refrigerate the casserole while preparing vegetables.
- 5
Brown ground pork in a large skillet over medium heat. Add onion, garlic, sage, thyme, brown sugar, and red pepper flakes. Cook until pork is browned and cooked through. Transfer to a bowl.
- 6
In the same skillet, cook sliced mushrooms over medium heat for about 10 minutes. Remove and set aside to cool.
- 7
Add spinach to the pan and cook over low heat until wilted, about 4 to 5 minutes. Set aside.
- 8
Remove casserole from refrigerator. Layer potatoes on top of soaked bread.
- 9
Spread cooked pork over the potato layer.
- 10
Top with mushrooms and spinach.
- 11
Layer another shingle of potatoes on top.
- 12
Pour remaining egg mixture over all layers and lightly press down to ensure custard coats everything and fills gaps.
- 13
Cover with foil and bake until a knife easily pierces the potatoes, 50 to 60 minutes.
- 14
Uncover, top with cheese, and return to oven until cheese is melted and bubbling, 6 to 8 minutes.
- 15
Top with fresh herbs if desired while warm.
Tips
Dry the bread thoroughly at low temperature to prevent a soggy casserole while maintaining the bread structure.
The initial soak with half the custard allows the bread to absorb flavor before the vegetable layers are added.
Do not rinse the skillet between cooking pork and mushrooms to retain flavor buildup.
Good to Know
Cover and refrigerate up to 3 days. Reheat covered in a 180C oven until warmed through.
Assemble through step 4 and refrigerate overnight. Proceed with vegetable preparation the next morning before baking.
Serve warm directly from the casserole dish. Garnish with fresh chives, thyme, or parsley.
Common Mistakes
Use low temperature when drying bread to avoid browning, which creates hard edges.
Press bread down only lightly after soaking to avoid compressing it into a dense mass.
Do not skip the cooling step for cooked vegetables before layering to prevent premature cooking of eggs.
Ensure all layers are evenly distributed to promote uniform cooking throughout the casserole.