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Caramelized Onion Frittata

  • Serves: 8
  • Prep Time: 30 min
  • Cook Time: 10 min
  • Calories: 196
caramelized onion frittata in a blue cast iron skillet topped with baby kale, feta and caramelized onions

A silky pour of heavy cream helps this vegetable-laden frittata stay tender, light and bouncy, even as we load it up with rich caramelized onions, tangy feta and a veritable garden of baby kale.

A Whole Lotta Frittata

Thie easy breakfast frittata is rich with cream and caramelized onions—DIY, friends! They’re SO easy— and yet it still manages to get the “healthy-ish” stamp of approval, since our vegetable frittata recipe is packed with more baby kale than it is cheese and cream. Plus, with no crust (btw, crust vs. no crust is the difference between a quiche and a frittata), our frittata recipe is as low-carb as they come.

slice of caramelized onion frittata on a wood spatula

What Is a Frittata?

Eggs + whatever you’ve got + oven= frittata. The Italian answer to a classic French omelette, a frittata is essentially a crustless quiche, and while they make a wonderful breakfast, they’re great for dinner, too. At its core, a frittata is really just a thrifty, easy way to use up leftovers—take whatever bits and pieces you’ve got lurking around your fridge, toss them in a big (oven-safe) skillet with some whisked eggs, bake and call it brunch (or breakfast, or dinner). Classic Neapolitan pasta frittata is a great (and oh-so-Italian) example of this, but our recipe keeps things a little healthier than that—no pasta, here.

blue cast iron skillet with sautéed baby kale
blue cast iron skillet with sautéed baby kale and caramelized onions
blue cast iron skillet with caramelized onions and baby kale with beaten eggs being poured over the top
caramelized onion and kale frittata baked in a blue cast iron skillet

How To Make a Frittata:

Frittata is a forgiving dish, and our recipe is no exception. Think of our frittata recipe as a template to which you certainly do not have to stick closely. Maybe make it our way the first time, so you know how a frittata works. Once you’ve mastered our basic baked frittata recipe, feel free to change it up! Here’s what to do:

  1. Give eight eggs a really good whisk.
  2. Add cheese (we love feta for this) a pinch of salt, pepper and heavy cream to the eggs. The heavy cream is a “nice to have”, not a must. If you don’t have it, skip it! Your frittata will still be delicious.
  3. Sauté the baby kale in olive oil (not extra virgin). You could also use regular kale here—just remove the tough stems and slice it into ribbons.
  4. When the kale is wilted, and the pan is coated with a good slick of olive oil, add the caramelized onions and the whisked eggs and dairy to the pan.
  5. Let the frittata begin to set a bit, and then move it to the oven to finish.
  6. When it’s puffy and just-set in the middle, it’s done!
caramelized onion frittata in a blue cast iron skillet with one slice removed

What To Serve with Frittata

We love to serve this with a simply-dressed green salad as a healthy, elegant brunch. Whatever your favorite breakfast potatoes are—crispy roasted potatoes, for example—would also be a great frittata side dish. Just don’t forget the coffee and mimosas!

Tools You’ll Need to Make a Frittata:

wooden plate with a slice of caramelized onion frittata served with a fresh arugula salad

Other Any-Time-of-Day Egg Recipes:

We go through eggs by the two-and-three dozen—how about you? Healthy, high in protein, quick to cook and so versatile, they’re just the best. Here are three recipes we whisk up on the regular:

How’d It Go Over?

We’d love to know! Snap a photo of your caramelized onion, feta and baby kale frittata, and maybe even a video of the beautiful people you feed it to. Tag us on Instagram using @themodernproper and #themodernproper. Happy eating!

Caramelized Onion Frittata

  • Serves: 8
  • Prep Time: 30 min
  • Cook Time: 10 min
  • Calories: 196


  • 8 Eggs, beaten
  • 1/3 cup Heavy cream
  • 1 tsp Salt
  • 1/2 tsp Ground pepper
  • 1/4 cup Fresh chives (optional)
  • 2 tbsp Olive oil
  • 1 cup Caramelized onions
  • 4 cups Baby kale (5oz)
  • 6 oz Feta, crumbled, divided


  1. Preheat oven to 400°F.
  2. In a large bowl add the beaten eggs, cream, salt, pepper, chives and 2/3rds of the feta cheese.
  3. In a 10 “ skillet Oven safe skillet heat olive oil over medium heat. Add in kale and sauté for for 1 minutes or until wilted. Add in the caramelized onions, breaking them up until they are mixed with the kale. While still over the heat carefully pour in the egg mixture and let the edges set (untouched) for 2 minutes.
  4. Bake on center rack for 10 minutes or until eggs have completely set. Top with remaining feta and fresh chives if you have them! Serve warm (or cold) with a green salad or roasted potatoes.

Nutrition Info

  • Per Serving
  • Amount
  • Calories 196
  • Protein 10 g
  • Carbohydrates 6 g
  • Total Fat 14 g
  • Dietary Fiber 1 g
  • Cholesterol 189 mg
  • sodium 718 mg
  • Added Sugars 3 g

Caramelized Onion Frittata

Questions & Reviews

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  • Rebecca Koses

    This recipe was DELICIOUS and a repeat!