Christmas mornings are a curious blend of frenzy and magic in our home. The children run down the stairs to admire the tree and gaze in awe at the piles of ribboned gifts that appeared overnight. And, I don’t want to miss a thing. That’s why every Christmas, I make a special brunch – one that takes almost no energy because it’s all been prepared ahead. And the center every Christmas is a super simple, Make-Ahead Breakfast Casserole.
Packed with vegetables and good quality sausages, it pairs beautifully with a light fruit salad. And all you have to do is tuck it in the oven about 30 minutes before you plan to eat.
What is a breakfast casserole?
A breakfast casserole is an egg dish that you can make ahead for breakfast. Most casseroles include cheese, vegetables, meat and a starch like potatoes or bread.
They’re easy to prepare and can feed a crowd. In addition, breakfast casseroles reheat very well. So, you can easily make it ahead, tuck it in the freezer and then reheat it when you’re ready to serve family and guests. Accordingly, it’s a perfect dish to serve for holiday brunches. That way, you’ll spend more time with your loved ones and less time in the kitchen.
What’s the formula?
Make-ahead breakfast casseroles sometimes develop a rubbery texture when they’re over-baked either during the initial bake, or when reheated. So, for smooth texture follow a ratio of 1 whole egg to ½ cup cream or other dairy. It’s that easy.
In addition, make sure to cook most of the water out of the vegetables you add to the casserole. That way they won’t leak water into the casserole and break your custard. If you keep to the rules, you’ll have a gorgeous casserole every time you bake.
Freezing, Sealing and Reheating
By making a breakfast casserole ahead, you’ll save loads of time in the morning and can spend more of that time with your friends and family – and less in the kitchen. That’s because the work’s already done.
To make it in advance, you’ll first prepare the egg casserole and bake it as you normally would. And then you’ll freeze it. For the best results, use a double-freeze method that allows you to vacuum seal the casserole. As a result, your casserole will stay fresh longer and taste better. Plus, you won’t have to worry about freezer burn.
First, bake your casserole and allow it to cool to room temperature on the countertop. Next, tuck the casserole, pan and all, in the freezer. Allow to freeze until just solid – about 2 hours. Next, vacuum seal the casserole in its pan. Return it to the freezer where it should keep up to 1 year.
The night before you plan to serve the breakfast casserole, let it thaw in the fridge. Next, sprinkle it with cheese, tent it with foil and let it come to temperature in the oven.
- 1 ½ Quart Baking Dish
Make the Breakfast Casserole.
- Heat the oven to 350 F.
- Warm the olive oil in a skillet over medium heat, and then toss in the onions. Sauté them in the hot oil until deeply fragrant and beginning to caramelize, about 10 minutes. Stir in the breakfast sausage, and continue cooking with the onion until cooked through and well browned – about 8 minutes. Toss in the mushrooms, and sauté until browned and cooked through. Turn off the heat and allow the filling to cool.
- Whisk the eggs with sour cream, salt, pepper and green onions together with half the grated cheese.
- Spoon the filling into a baking dish, and then pour in the egg mixture. Bake for 45 minutes, until puffed with a slightly wobbly center. Allow the casserole to cool to room temperature, and then transfer to the freezer at least 2 hours and up to overnight.
Prepare the casserole for long-term freezing.
- Remove the casserole from the freezer, and sprinkle it with the remaining cheese. Tuck the casserole in its dish into a FoodSaver vacuum seal bag, and vacuum seal. Transfer to the freezer, and serve within 1 year.
Finishing the casserole.
- The night before you plan to serve the casserole, transfer it from the freezer to the fridge. Let it thaw, refrigerated, at least 8 hours and up to 24 hours.
- Heat the oven to 350 F, and place the casserole on a baking sheet. Tent with foil, and bake for 30 minutes, or until the casserole reaches an internal temperature of 160 F.
- Turn on the broiler to high, and remove the foil. Allow the cheese to brown under the broiler, 3 to 5 minutes. Serve warm.
Once you get the hang of this Make-Ahead Breakfast Casserole, you can adjust the basics – adding different cheeses (or none at all) and choosing new seasonal vegetables, too. Always remember to keep cook the vegetables well to keep your custard from breaking.
- Sundried Tomatoes, Goat Cheese and Thyme work well in place of sausage and mushrooms. Chop the tomatoes finely for the best texture.
- Kale, Garlic and Potatoes go well together. Just remember to cook your kale well, and give it a squeeze to reduce the water content before you toss it in with the eggs.
- Bacon and Onion are a classic combination, especially when paired with full-flavored Gruyere cheese.
- Spinach and Smoked Salmon are also a nice combination. Remember to give your spinach a squeeze to reduce its liquid.