Make-Ahead Baked Greek Omelet

updated Feb 3, 2020
Make-Ahead Spinach and Feta Egg Casserole
Filled with leafy spinach and chunks of crumbled feta, and laced with fresh dill, this egg casserole will remind you of spanakopita.


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(Image credit: Joe Lingeman)

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Spinach and feta make eggs even better with a fresh, salty, and creamy kick. But with this make-ahead breakfast casserole, that’s just the beginning. In addition to lots of leafy greens and chunks of crumbled cheese, this casserole is laced with fragrant fresh dill, sweet red pepper, and a dollop of Dijon for a subtle tang. After your first bite, you might start wondering what this reminds you of — it’s spanakopita, friends.

A Greek-Inspired Make-Ahead Egg Casserole

The beauty of this breakfast egg casserole extends well beyond its veggie filling and ability to feed a crowd with ease. What I love just as much is the dish’s make-ahead potential.

Option one is to sauté the vegetables, stir in the herbs, and set the filling aside in the fridge up to three days ahead until you’re ready to fully assemble and bake. Option two is to prep and assemble the whole thing the night before, so all that’s left to do in the morning is pop your casserole into the oven. You can even freeze the unbaked casserole for several months — you’ll just need to add a little extra time when baking.

(Image credit: Joe Lingeman)

As with all recipes I make with feta, I can’t recommend starting with a block of feta strongly enough. Yes, the crumbled stuff is convenient, I’ll give you that, but when it comes to quality and taste, a good block of feta (go for the ones sold in brine) cannot be beat for its fresh, pronounced flavor.

Tester’s Notes

I firmly believe that having a great egg casserole in your back pocket that also can be made ahead of time is the secret to conquering breakfast. This version has quickly become my new favorite. It’s filled with vegetables and has enough feta and chopped fresh dill in it to inspire your next vacation to Greece. I added the option of using frozen spinach in place of fresh, if you happen to already have some tucked away in your freezer.

Sheela, January 2018

Make-Ahead Spinach and Feta Egg Casserole

Filled with leafy spinach and chunks of crumbled feta, and laced with fresh dill, this egg casserole will remind you of spanakopita.

Serves 8

Nutritional Info


  • 1 tablespoon

    olive oil, plus more for the baking dish

  • 1/2

    medium yellow onion, diced

  • 1/2

    medium red bell pepper, cored, seeded, and diced

  • 1 1/2 teaspoons

    kosher salt, divided

  • 6 ounces

    baby spinach (about 6 cups packed), or 8 ounces frozen spinach, thawed, drained, and pressed well to remove liquid

  • 2

    cloves garlic, minced

  • 2 tablespoons

    chopped fresh dill

  • 12

    large eggs

  • 2 cups

    whole or 2% milk

  • 1 tablespoon

    Dijon mustard

  • 1/4 teaspoon

    freshly ground black pepper

  • 4 ounces

    feta cheese, crumbled (about 1 cup)


  1. Arrange a rack in the middle of the oven and heat to 375°F. Coat a 9x13-inch baking dish with olive oil.

  2. Heat the oil in a large frying pan over medium heat until shimmering. Add the onion, pepper, and 1/2 teaspoon of the salt. Cook, stirring occasionally, until softened, about 5 minutes. Add the spinach and garlic, and toss until wilted and almost all of the liquid is evaporated, about 3 minutes. Remove from the heat and stir in the dill. Transfer to the baking dish and spread in an even layer.

  3. Place the eggs, milk, mustard, remaining 1 teaspoon salt, and pepper in a large bowl and whisk until the eggs are completely broken up and incorporated. Pour over the spinach mixture in the baking dish. Sprinkle evenly with the feta.

  4. Bake until the top is light golden-brown and a knife inserted in the middle comes out clean, 40 to 45 minutes. Let cool for 5 minutes before slicing.

Recipe Notes

Make ahead: The casserole can be assembled, covered tightly with aluminum foil, and refrigerated overnight before baking. Uncover before baking.

Freezing: The casserole can also be frozen unbaked. Cover tightly with aluminum foil, wrap in plastic wrap, and freeze for up to 3 months. Thaw overnight in the refrigerator, then proceed with baking uncovered as instructed. Depending on how frozen the casserole still is, it may take up to 1 1/2 hours baking time; check after 1 hour.

Storage: Leftovers can be stored in an airtight container in the refrigerator for up to 4 days.