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Make an EASY Crustless Spinach Quiche with caramelized onions for brunch! This is the perfect egg casserole recipe and it’s so easy to make because it doesn’t have the crust.
This crustless quiche is so good you won’t miss the crust!
Best Crustless Quiche Recipe
There are so many reasons to love this crustless spinach quiche! It’s easy to make, super flavorful, and it’s also low-carb. It’s such an easy dish for weekend brunch, holidays, or just because you are craving an egg casserole.
We love this Crustless Quiche recipe because it’s full of spinach and caramelized onions and I know you’ll love it too.
Table of Contents
Ingredients in a Crustless Quiche Recipe
A basic quiche filling includes eggs and milk. A quiche is an unsweetened custard pie, and custard is made with eggs and milk. Usually, quiche also has some sort of vegetable and cheese in it as well. The ratio of eggs to milk is 1 egg to 1/2 cup milk. It might seem like there’s a lot of milk in the recipe compared with the eggs, but that’s what makes that custard filling.
Basic Quiche Ingredients:
- Eggs: 3 large eggs for this recipe
- Milk: following the above ratio we’ll need 1 1/2 cups milk
- Spices: salt and pepper for flavor, add other spices you love!
What’s the best quiche filling?
Really, that’s up to you. I absolutely love this combination of caramelized onions and spinach; all three make this an easy vegetarian egg dish. Caramelizing the onions takes a little bit of extra time, but it’s so worth it: the caramelization gives them a sweetness and softness unparalleled by just sautéing them.
If you skip caramelizing the onions this becomes a quick crustless quiche recipe, so do what you prefer!
Spinach Crustless Quiche Ingredients:
- Frozen Chopped Spinach: be sure it’s thawed and drained well
- Mozzarella Cheese: you can use any kind of shredded cheese you like
- Onion: caramelized onions takes the flavor to another level
How to make Crustless Spinach Quiche
1. Caramelize the Onions: cook the onions, stirring often, until they’re brown and caramelized, about 15-20 minutes. Remove from heat to cool.
2. Drain Spinach: Remove spinach from box and place in several layers of paper towels or a clean kitchen towel. Squeeze out all the water from the spinach.
3. Mix: Whisk eggs and milk until frothy. Stir in the spinach, onions, cheese, salt, and pepper.
4. Bake: Pour into prepared pan. Bake 35-45 minutes, or until it’s browned and no longer jiggly. (If you have an instant thermometer, it should read about 170°F internal temperature when it’s done.)
Tips for how to make crustless quiche:
- Be sure to squeeze all the liquid out of the spinach. Defrosted frozen spinach has a lot of water in it. Wrap the bundle in a few paper towels or a clean kitchen towel and ring it out to get all the liquid out of it.
- You can skip caramelizing the onions if you prefer, but make sure to at least sauté them.
- Don’t have a quiche pan? Use a 9-inch pie plate.
- I used mozzarella cheese but Swiss, Gouda or Gruyere would be fantastic too.
How do you store crustless quiche? Quiche is best served warm right after it’s made and allowed to set for a few minutes. Reheated eggs aren’t the best, but if you do have leftovers, just heat them in the microwave for about 30 seconds.
What pan is best for quiche? If you have one, use a 9-10″ tart pan (with removable bottom) for easy serving. If not, use a 9-10″ pie plate (or deep dish 9-inch).
How long to cook a crustless quiche? This recipe takes about 35-45 minutes.
How do you know quiche is done baking? It’ll be slightly golden on top and no longer wet looking, and slightly jiggly but will not wave when tapped.
How to freeze Crustless Quiche? You can freeze it whole or slice cooled quiche into portions and freeze individually in sandwich size bags.
Other Recipes To Try
Spinach Crustless Quiche
- 1 tablespoon olive oil
- 1 small yellow onion diced
- 1 (10 ounce) box frozen chopped spinach thawed
- 3 large eggs
- 1 ½ cups milk
- 1 cup mozzarella cheese shredded
- ¼ teaspoon salt
- ¼ teaspoon ground pepper
- Place a medium sized frying pan over medium-low heat. Add olive oil and swirl in the pan. Add the onions and cook, stirring often, until they’re brown and caramelized, about 15-20 minutes. Remove from heat to cool.
- Preheat oven to 350°F. Spray a quiche pan (or 9-inch pie pan or square baking dish) with nonstick cooking spray.
- Remove spinach from box and place in several layers of paper towels or a clean kitchen towel. Squeeze out all the water from the spinach. Remove towel.
- Whisk eggs and milk until frothy. Stir in the spinach, onions, cheese, salt, and pepper.
- Pour into prepared pan. Bake 35-45 minutes, or until it’s browned and no longer jiggly. (If you have an instant thermometer, it should read about 170°F internal temperature when it’s done.)
- Cool slightly then serve. Store leftovers in refrigerator. Best eaten the day it’s made.
- Be sure to remove all the excess water from the spinach when squeezing it.
- Use any cheese you like!
- Quiche is done when it’s lightly golden, no longer wet, and jiggles when tapped (instead of rolling like waves).
**Did you make this recipe? Don’t forget to give it a star rating below!**
Crustless Quiche is so easy to make with spinach and caramelized onions. Spinach Crustless Quiche is a great brunch recipe and it’s so good!
Last Updated on May 20, 2022
I made this and loved it. I am cooking for two people with dietary restrictions, do you think it could work without the yummy cheese?
I haven’t tried it without cheese but I think it will be just fine without it.
Thank you. We have a former vegan, now vegetarian and a gluten free, sugar free, pescatarian who of course can’t eat all fruits and veggies. I’m being challenged to say the least.
I cut back some on the milk as I used 1%. I also used fresh leaf spinach and added some extra spices like garlic and Italian seasoning. I did not have mozzarella cheese but used the Mexican blend from food lion. I also added bacon bits. As an added treat, I added some Texas Pete upon serving. This was a great recipe. ! Yum !
This was soooo good! I subbed for items I had on hand- your ratio of eggs to milk is perfect, it cooked up light and fluffy!
can i use brocoli instead of spinach you think?
It was pretty good, but I am partial to the crust. It would’ve tasted even better with crust!
This quiche looks wonderful, but I’d really like to put it on a crust. Will this recipe make it too soggy?
The easiest and best Quiche ever! I used fresh spinach and added mushrooms and bell peppers. Love it
How to substitute tri-color peppers for the 10 oz, box spinach in the 9in. pie pan.
Thank you, I want to do this for Christmas morning.
This looks absolutely delicious, and so easy to make!!
I make several crustless quiches with a biscuit mix. When I was in my 20,s they were called Bisquick impossible pies. They are usually a mixture of meat, vegetables and cheeses of your choice. You then pour the the biscuit mix of eggs (3),milk and salt & pepper. Add some more cheese and bake for 25 minutes then add more cheese cake until it melts (5 min). Let stand 10 minutes. Great when you have leftovers to use.