Make Ahead Breakfast Casserole

This make ahead breakfast casserole is vibrant with vegetables and savory cheese and is the dish I always turn to when I want something easy and impressive for a holiday brunch or a busy weekday morning. The combination of eggs creamy cheese and colorful veggies makes it hearty and satisfying. You can prepare it all the night before so breakfast is just a quick bake away.

I remember making this on Christmas Eve and feeling relaxed the next morning just popping it in the oven while everyone opened gifts. It became a new family tradition.

Ingredients

• Extra virgin olive oil: gives a rich flavor and helps sauté the vegetables Choose the freshest oil you have for best taste
• Red onions: give a subtle sweetness and pop of color Use firm onions with papery skin
• Broccoli: adds crunch and is loaded with nutrients Look for bright green florets
• Mushrooms: lend a savory earthiness Select mushrooms that are dry and firm
• Cherry tomatoes: provide freshness and a juicy bite Choose plump and shiny tomatoes
• Fresh spinach: wilts perfectly and brings vitamins and color Pick vivid dark green spinach without wilting
• Eggs: form the creamy base Use high quality free range eggs if possible
• Almond milk: makes the dish lighter Choose unsweetened almond milk for best results
• Garlic powder: enhances overall flavor Use fresh garlic powder without clumping
• Mustard powder: is optional but it brings a hint of tang Pick a fine powder for even distribution
• Salt and pepper: elevate all the flavors Opt for fresh cracked pepper
• Cheddar and mozzarella cheese mix: melts into a gooey topping Use cheese that is freshly grated for better melt
• Parsley: is optional for a fresh colorful garnish Fresh flat leaf parsley is ideal

Step by Step Instructions

Prepare the Baking Dish:

Lightly spray a nine by nine inch casserole dish with cooking spray and set it aside to prevent sticking

Sauté the Onions:

Pour extra virgin olive oil into a medium skillet set over medium heat Add chopped red onions and let them cook for about five to six minutes stirring often until they soften but do not brown This develops a gentle sweetness

Cook the Vegetables:

Add chopped broccoli sliced mushrooms cherry tomatoes and fresh spinach to the skillet Sauté for another six to eight minutes until the vegetables are tender but not falling apart This releases their flavors and moisture

Transfer Veggies:

Spoon the sautéed vegetables evenly into the prepared baking dish spreading them out in a colorful layer

Whisk the Eggs:

In a large bowl crack the eggs and whisk thoroughly Add almond milk garlic powder mustard powder salt and pepper Continue whisking until the mixture is well combined and slightly frothy This ensures the eggs bake up fluffy

Combine Mixtures:

Pour the egg mixture gently over the vegetables in the baking dish allowing the liquid to seep down and coat everything

Add the Cheese:

Sprinkle the cheddar and mozzarella cheese evenly across the top forming a generous layer

Bake Covered:

Cover the casserole dish with foil Slide into a preheated oven at three hundred twenty five degrees Fahrenheit and bake for forty minutes This gently cooks the eggs without drying them out

Bake Uncovered:

Remove the foil and return the dish to the oven for an additional ten minutes This step helps the cheese melt perfectly and creates a golden top

Cool and Serve:

Take the dish out of the oven and let it cool for about five minutes before cutting and serving This makes slicing easier and lets the flavors settle

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Cheddar brings the nostalgic comfort to this dish for me My mom always used extra and it made the casserole bubbly and irresistible We would gather in the cozy kitchen and dig into big slices before tackling a busy day

Storage Tips

This breakfast casserole keeps well in the refrigerator for three to four days Once cooled cover it tightly with plastic wrap or transfer portions to airtight containers For an even longer shelf life freeze individual slices wrapped well in foil and reheat straight from the freezer at three hundred fifty degrees Fahrenheit until warmed through

Ingredient Substitutions

You can swap almond milk for regular milk or oat milk For vegetables use whatever you have on hand bell peppers zucchini or asparagus work great Swap cheddar for pepper jack or feta for a different flavor Cheese is very forgiving in this casserole

Serving Suggestions

Serve warm squares as is or with a spoonful of salsa for a lively kick A side of fresh fruit or a crusty piece of toast pairs perfectly If you are feeding a crowd offer hot sauce and extra fresh herbs on the side

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Cultural Context

Breakfast casseroles are a classic in American brunch culture perfect for holidays and family gatherings Their adaptability comes from the tradition of using whatever is available in the fridge making them a symbol of practical and comforting home cooking

Recipe FAQs

→ Can I prepare this bake the night before?

Yes, you can assemble everything ahead, refrigerate overnight, and bake fresh in the morning.

→ What vegetables work best for this dish?

Broccoli, mushrooms, cherry tomatoes, and spinach are used here, but you can add peppers or zucchini to taste.

→ Is it possible to make this dairy-free?

Absolutely! Swap the cheese for a plant-based variety and use a non-dairy milk, such as almond milk as listed.

→ How do I store leftovers?

Leftovers keep well in an airtight container in the fridge for up to three days and can be reheated in the oven or microwave.

→ Can I freeze portions for later?

Yes, after baking, let cool completely, slice, wrap securely, and freeze for up to one month. Defrost and reheat as needed.