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This Crustless Spinach Quiche is the ultimate easy breakfast or holiday brunch dish! By skipping the crust, we make this recipe naturally gluten-free and incredibly simple to prep. The secret to the deep, savory flavor is the caramelized onions, which pair perfectly with the spinach and melted mozzarella cheese.
There are so many reasons to love a crustless spinach quiche! It’s easy to make and super flavorful. It’s such an easy dish for weekend brunch, holidays, or just because you are craving an egg casserole. Quiche typically has a crust, but this one doesn’t need it and I promise you will not miss it! (No crust also makes it gluten-free!) Plus, I used caramelized onions to make this the perfect cheesy savory brunch dish.
Quiche is very similar to a frittata but they are actually different. Quiche is mixed and baked in the oven, whereas frittatas are partially cooked on the stovetop and finished in the oven. The texture of the finished quiche is soft and perfect with the vegetables and shredded cheese.
Ingredients For a Flavorful Spinach Quiche
- I like using whole milk but you can also use nonfat or nondairy milk.
- Use frozen thawed spinach for ease – because spinach shrinks as it cooks you would need a lot of fresh spinach! Using frozen makes life so much easier (and it’s cheaper too).
- To ensure your quiche isn’t watery, you must squeeze out all the water from your thawed spinach using paper towels or a clean kitchen towel. Removing this excess moisture is the key to getting a perfect, firm texture that isn’t soggy.
- You can use any kind of shredded cheese you like: gruyere cheese, cheddar, parmesan cheese, or Swiss cheese are all good options, but I love freshly shredded mozzarella for this recipe.
- Caramelized onions take the flavor to another level. It’s super simple to cook onions this way.
- Don’t have a quiche pan? That’s ok! Use a 9-inch pie plate or a 9-inch square cake pan instead.
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Dorothy’s Expert Tips for 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 do not need to caramelize the onions–it is totally up to you. If you don’t caramelize them, make sure to at least sauté them.
- How to know when quiche is done baking: If you have an instant thermometer, it should read about 170°F internal temperature when it’s done.
Spinach Crustless Quiche Recipe
Recipe Video
Ingredients
- 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
Instructions
- 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.
Recipe Notes
- 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).
Recipe Nutrition
How to make Crustless Spinach Quiche
- Place a large skillet over medium-low heat. Cook onions in olive oil for about 15-20 minutes, stirring often, or until they’re caramelized.
- Preheat oven to 350°F. Spray a quiche pan (or 9-inch pie dish 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 in a large bowl until frothy. Stir in the spinach, onions, cheese, kosher salt, and black pepper.
- Pour egg mixture into prepared pan. Bake 35-45 minutes, or until it’s browned and no longer jiggly. Cool slightly then serve.
Serving Suggestions and Variations
- Serve quiche with a simple side salad or a vegetable like air fryer broccoli or roasted carrots.
- Serve along side bacon or sausage.
- Roasted potatoes are delicious anytime of day.
- Want to add other vegetables? Use any pre-cooked vegetable like bell peppers, broccoli, asparagus, or mushrooms.
- Add ham to make it more like quiche lorraine.
FAQs
Store covered with plastic wrap or in an airtight container. If you want to have it for leftovers, just reheat for about 30 seconds. Remember that reheated eggs are not always the best so it would be best to eat all on the first go.
You can freeze it whole or slice cooled quiche into portions and freeze individually in sandwich size bags for up to 2 months.
A quiche is mixed and then baked in the oven, whereas a frittata is typically started on the stovetop and finished under the broiler.
Make sure to squeeze all the water out of your thawed spinach before adding it to the egg and milk mixture.
Yes! This recipe works perfectly in a 9-inch pie pan, a quiche pan, or even a square baking dish.
The quiche is done when it is lightly browned and the middle is no longer jiggly; it should reach an internal temperature of about 170°F.
It’s delicious but I added a touch of nutmeg…
Glad you like the recipe, Carla!
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