Frittatas are basically crustless quiches. They are light, fluffy, and thick when made well. This version is filled with caramelized onions, mushrooms, baby spinach, and Gruyere cheese for a savory breakfast, brunch, or light dinner.
A well-made frittata is inexpensive, easy to prepare, quick-cooking, and a great way to use up leftover vegetables, meats, or cheeses. It can also be served for almost any meal, from breakfast to dinner.
The key is getting the texture right. A good frittata should be tender and set, not watery, rubbery, or overly dense. A few simple tips can help you get the right egg-to-dairy ratio, height, and flavor.
Here are some tips to help you make the most of your frittata:
1. Use Full-Fat Dairy
Do you technically have to add dairy? No, but a little dairy helps make the frittata softer and creamier. Whole milk, half-and-half, sour cream, yogurt, or crème fraîche can all work well. For the best texture, use full-fat dairy instead of low-fat or fat-free versions.
2. Get the Right Ratio
Frittatas are simple, but proportions matter. For every dozen eggs, use about ½ cup of dairy. Too much dairy can make the eggs loose and difficult to set, while too little can make the frittata taste dense and overly eggy.
3. Use The Right Skillet
A well-seasoned cast iron skillet works especially well for frittatas, but any oven-safe skillet or baking dish can work. You can use a small skillet, pie plate, or square 9×9-inch pan, as long as it is safe to go in the oven.
Size matters, too. A 12-egg frittata works well in a 10-inch skillet because it has enough surface area to cook evenly while still keeping some height. A larger pan will create a thinner frittata.
4. Cook the Vegetables First
A frittata is a great way to use up leftovers. Cooked mushrooms, onions, peppers, sausage, or roasted vegetables can all be added.
If you are using raw vegetables, especially firmer ones like onions or peppers, cook them first. They will not soften much once the eggs are added and baked. Pre-cooking them in a little oil also adds flavor and helps remove excess moisture.
You can also add extra flavor with garlic, chili powder, cumin, or your favorite herbs.
5. Season and Whisk Well
Season the eggs before cooking to bring out their flavor. Sea salt and freshly ground black pepper work well.
Once seasoned, whisk the eggs thoroughly so the mixture is smooth and slightly airy. This helps create a lighter, fluffier frittata.
Whether you are serving this frittata for breakfast, brunch, lunch, or dinner, it pairs well with a simple green salad or fresh fruit. You can also adjust the ingredients based on what you have on hand. Swap the Gruyere for another cheese, or add leftover roasted vegetables for a different version.
Store leftovers in the refrigerator and reheat gently so the texture stays tender.
CARAMELIZED ONION, MUSHROOM, SPINACH AND GRUYERE FRITTATA
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Caramelized Onion, Mushroom, Spinach and Gruyere Frittata
Description
Frittatas are basically crustless quiches. They are light, fluffy, and thick when made well. This version is filled with caramelized onions, mushrooms, baby spinach, and Gruyere cheese for a savory breakfast, brunch, or light dinner.
Ingredients
- 12 large eggs
- ½ cup half and half (or whole milk with a splash of heavy cream)
- 1 large onion, sliced
- 8 oz baby bella mushrooms,
- 2–3 cups fresh baby spinach, stems removed and roughly chopped
- 2 cups Gruyere cheese, shredded
- 2 tablespoons salted butter
- 2 tablespoons olive oil
- 1 teaspoon sea salt
- ½ teaspoon freshly ground black pepper
- ½ teaspoon paprika
- ½ teaspoon dried oregano
- ½ teaspoon thyme
- ⅛ to ¼ teaspoon red pepper flakes
Instructions
- Preheat oven to 375° F.
- Slice the onion into thin strips and saute in a 10″ cast iron skillet along with 1 tablespoon of oil and 1 tablespoon of butter. Season generously with salt as it will help the onion sweat and caramelize. Allow to saute for 35-40 minutes until very tender, stirring frequently until a deep brown color is achieved. Set aside ¼ cup of the onions.
- Add the sliced mushrooms and cook for an additional 5 minutes or until all the liquid has been released and evaporated.
- Add the chopped spinach to the skillet and cook for just a minute until spinach is tender.
- In large bowl, whisk together eggs, cream or milk, salt, pepper, paprika, thyme, oregano, and red pepper flakes, if using. Whisk well until eggs are frothy. Add the shredded cheese and stir to combine. Pour the egg mixture into cast iron skillet and top the frittata with the reserved onions.
- Carefully put the frittata in the preheated oven on the middle rack and bake for 22-25 minutes until middle is set but not overcooked. The frittata will continue to cook in the skillet when you take it out of the oven so do not overcook. Allow to cool 10 minutes before serving.
- Top with sour cream, avocado or chives.
WHAT TO SERVE WITH THIS:
Homemade Crispy Diced Homefries
Wow, this was SO flavorful!! Followed the recipe exactly and it came out beautifully. Definitely a keeper.
Hi! I am thinking of making this for a potluck brunch and was wondering if it would work well to make it one of those aluminum pans (instead of a skillet, which would be difficult to transport)! Also, how many servings does the recipe yield? Thank you!
I agree with others. This was a very well made frittata. I like Debi’s explanation of ratios, most food blogs don’t tell you things like that. She explains things well. Great recipe.
Made this for a brunch with my girlfriends and it was a hit! People went in for seconds. Absolutely delicious! And super easy to make. The most difficult/time-consuming part of the process was caramelizing the onions, and even that wasn’t hard. Will be making this again for sure.
I’m so glad to hear it Jenna!
What’s the serving amount for this recipe?
Wanted a frittata recipe instead of a quiche. Boy am I glad I did. Excellent, easy recipe that’s delicious.
Will be back to site, as I liked the design and layout of recipes on her blog.
Thank you!
thanks Doug. I hope you find many recipes that you like.