Denver Omelet Casserole
by Sommer Collier — on Apr 27, 2026 I love omelets, but making them one at a time for a crowd is never my idea of fun. That’s why I make this Omelet Casserole instead—it has all the best parts of a classic Denver omelet, from ham, peppers, onions, and cheddar cheese, baked together in one easy pan. I get all that fluffy texture and melty cheese, but with way less work and enough to feed everyone.
If you love a classic Denver omelet, then you’re going to go nuts over this protein-packed dump-and-bake casserole with ham, onions, peppers, and cheese! I recently shared our easy Denver omelette recipe, something you can make in just minutes on the stovetop. However, when making omelettes, you generally make one at a time. Today I’m showing you how to make a whole bunch of omelets at once, that you can cut into squares and serve to a crowd. It bakes up in under an hour, and is perfect to serve warm with all kinds of Tex-Mex-type condiments and side dishes!
Table of Contents
Sommer’s Recipe Highlights
Fluffy and Flavorful – This breakfast casserole has the most delightfully spongy, tender, and fluffy eggs. Then you also have incredible sweet and savory southwest flavors from the ham, bell peppers, onions, and cheese… lots of cheese. Seriously, the taste and texture are practically the same as a perfectly cooked Denver omelet!
Protein Powerhouse – A trifecta of eggs, ham, and cheese makes this baked Denver casserole packed with protein. It has about 13 grams of protein per slice! And with no potatoes or bread, the recipe is relatively low carb when compared to many classic breakfast casseroles, like my ham and egg bake (which is delicious, no doubt!)
Plenty to Share – As I mentioned above, this baked Denver omelet is one of those fabulous breakfast casseroles that can feed up to a dozen people. Or make a large pan for just a few people, and save the other half for quick breakfasts throughout the week.
Key Ingredients and Tips
- Butter – I prefer to use butter instead of oil to saute the veggies. It creates a richer flavor when sautéing the onion and peppers.
- Eggs – I use large eggs. But first, I set them on the counter for 15 minutes, or so, to get them closer to room temperature. Eggs that are too cold can slow down the cooking process.
- Veggies – I’m using the classic “must have” ingredients that make a true Denver omelet: White onion (I like that it has a bit of bite, but you can use yellow for a slightly sweeter taste), green bell pepper, and minced garlic.
- Ham – This is a great recipe for using up cooked and cubed leftover spiral ham from occasions like Christmas, Thanksgiving, or Easter. Or you can buy a precooked ham from the store, specially for this recipe.
- Cheese – I use shredded cheddar cheese. I always recommend shredding your own cheese by hand for the best flavor and to avoid any filler preservatives.
- Half & half – Sure, you can use whole milk. But the casserole won’t be as fluffy, so if you can, stick to the original recipe here and use half & half.
- Seasonings – I’m just using salt, pepper, and crushed red pepper flakes (but you can nix them if you’re sensitive to heat)
How to Make
Find the full ingredient proportions, detailed instructions, storage tips, and a video tutorial in the printable form at the bottom of the post.
Chop and Prep – I start by preheating the oven to 350 degrees. While it preheats, I spray the inside of a large 9×13-inch casserole baking dish with nonstick spray.
Then I chop the cooked ham, peel and chop the onion, remove the seeds and chop the bell pepper, and mince the garlic.
Lastly, I grate the cheese by hand, and set it aside.
Sauté Veggies – Next, I melt butter in a small skillet over medium heat. Don’t let it burn! Once it is hot, I toss in the peppers, onion, and garlic. Cook them for only a few minutes, while stirring with a spatula, just until the onions are a bit soft. Then I immediately turn off the heat and move the pan off of the burner.
The veggies will continue cooking in the baked omelet, so I try not to overdo it when sautéing, or they’ll get too soft.
Add Ham and Veggies to Baking Dish – While the onion, peppers, and garlic cool a bit in the skillet, I add the pieces of ham to the bottom of the baking dish. Next, add the vegetables and melted butter. Then I set the dish aside to let the veggies cool so the egg mixture doesn’t cook too quickly.
Make Egg Mixture – Speaking of the egg mixture, now it’s time to whip it up! I crack the eggs into a medium-sized mixing bowl (or large bowl) and add the half & half. I use my handy hand beater to beat them together vigorously, until the mixture gets super frothy. You can use a whisk, but it will take more elbow grease to get the right frothiness. Check out the picture below to see what I mean.
Then I beat in the salt, pepper, and crushed red pepper flakes, if you want a nice bit of heat. You know I do!
Add Cheese and Toss – I set the egg mixture to the side for a minute and check that the veggies in the casserole dish are cool. Then I add the shredded cheese to the pan, and use a large spoon to gently toss and combine the cheese with the ham, peppers, onion, and garlic. Spread these out in an even layer, without packing down too tightly. You might even give the pan a ‘lil jiggle to make some space between the cheese and veggies, so the eggs can get in every nook.
Pour the Eggs – Now I pour the frothy egg and cream mixture over the veggies, ham, and cheese. Go slowly as you move the mixing bowl back and forth across the pan so it’s evenly distributed. Again, shake the dish ever so slightly to work the eggs down in the dish.
Bake – Into the oven it goes! I bake the western egg bake for about 45 minutes, until the eggs have set and the top is golden brown. I know it’s done when I can see the edges start to separate from the sides of the pan. When I stick a knife in the middle, it should not come out not-eggy… There will be some cheesiness, to be sure, but the center of the casserole shouldn’t be wet. If it isn’t quite set, bake for another 5 minutes, and check again.
Expert Tips
The key to making this baked omelet incredibly flavorful and fluffy is to first sauté the onions, peppers, and garlic so they’re soft and sweet before adding them to the egg mixture. We don’t want rubbery onion texture in the final product, so don’t skip this step!
Second, beat the eggs well with half & half so they’re light and fluffy when they go in the baking dish. Otherwise, you’ll wind up with a texture that’s more like scrambled eggs. I use a hand beater, as I find this does a much better job of combining everything versus using a whisk.
Serving Suggestions
I serve portions of the baked Denver omelet with a sprinkle of sliced scallions, and with salsa and sour cream on the side. I have several salsa recipes on the site to try!
- Homemade Salsa Recipe (with nearly 5 stars from over 400 reviews)
- Roasted Tomato Salsa
- Avocado Salsa Verde
- Pico de Gallo
And, surprise surprise, I also enjoy my baked egg dish with a few dashes of spicy hot sauce.
There is plenty of protein and veggies packed in here already. But to make it part of a complete meal, you might consider also serving home fries, homemade hash browns, golden pan-fried potato cakes, or any of your favorite starchy and/or carb-y breakfast foods.
Storing and Reheating
Leftovers will be a bit denser when refrigerated and reheated, but still have a lovely, tender texture and southwest flavors. The casserole will keep well in an airtight container and stored in the refrigerator for up to 3-5 days.
You can freeze slices, too, but as I mentioned above, this will change the taste and texture. Wrap individual pieces in plastic wrap, then store all of the portions together in an airtight ziploc freezer bag. Freeze for up to 3 months, then take out and thaw slices in the fridge overnight.
A baked omelette is best reheated in the oven for 10-15 minutes at 350 degrees. If you need to microwave, you can do so in short 10-second bursts at 50% power. Just keep in mind that slices may be a bit moister and rubberier when microwaved.
Frequently Asked Questions
Not to be a broken record, buuut you really must sauté the veggies before assembling the western omelette casserole. This step cooks out any moisture from the vegetables. Otherwise, the moisture will leak into the egg base as it bakes, making it soggy.
Personally, I prefer to make and serve the casserole fresh, while the eggs are super fluffy. But you can prep everything the night before, keeping the sauteed veggies and ham separate from the egg mixture in the fridge. Then in the morning, whip the eggs, pour, and bake!
Sure! As-is, this recipe is made in a 9×13-inch baking dish, and yields 12 pieces. Halve the ingredients and bake in an 8×8 or 9×9-inch square pan for 6 servings.
Help Me Spread the Word about this Fabulous Free Recipe! Sharing this recipe link on Pinterest and Facebook is super impactful, and I greatly appreciate it! Find the share buttons below the recipe form.
More Breakfast Recipes
Denver Omelet Casserole
Video
Ingredients
- 3 tablespoons butter
- 1 cup diced onion
- 1 cup green bell pepper
- 2 cloves garlic minced
- 2 cups diced ham
- 12 large eggs
- 1 cup half & half
- 1 ½ cups shredded cheddar cheese
- 1 ½ teaspoon salt
- 1 teaspoon pepper
- ¼ – ½ teaspoon crushed red pepper flakes
Instructions
- Preheat the oven to 350°F. Set out a 9 x 13-inch baking dish and spray the inside with nonstick cooking spray. Chop and prep all ingredients.
- Set a small skillet over medium heat. Add the butter to the skillet. Once melted, add the diced onions, bell pepper, and minced garlic. Stir and sauté until the onions are very soft, 3-5 minutes. Then turn off the heat.
- Meanwhile, add the diced ham to the baking dish, followed by the sautéed vegetables. Scoop all the melted butter into the baking dish. Spread the veggies out and allow them to cool.
- Set out a mixing bowl, and crack the eggs into the bowl. Add the half-and-half, and beat well until the eggs are frothy. Then add the salt, pepper, and crushed red pepper flakes. Beat again to combine.
- Now that the veggies are cool, toss the shredded cheese into the ham and vegetable mixture in the baking dish. Spread the mixture out in an even layer. Then pour the egg mixture over the top of the other ingredients.
- Place the baking dish in the oven and bake for 45-50 minutes, until the center is puffed and the edges are golden brown. Allow the egg bake to cool for at least 5 minutes before serving. Serve as-is, or sprinkle with scallions, and serve with salsa and sour cream.
