2 Best Types of Sweet Onion Frittata + How To Make Them

#1 Asparagus and Sweet Onion Frittata

Since I started raising chickens, I have made frittatas at least once a week. If you have some eggs on hand and want to clear out your fridge, make a frittata! The basic technique is simple: prepare vegetables and fillings, spread them evenly in a skillet, top with well-beaten eggs, and finish cooking in the oven.

This recipe is for an asparagus version, but there are endless possibilities—broccoli and sharp cheddar; tomato, corn, and basil; roasted bell pepper and feta; even leftover spaghetti makes a wonderful frittata. They are delicious warm, at room temperature, or cold. Serve a frittata with a green salad, and you have an easy-to-prepare light dinner.

Ingredients Asparagus and Sweet Onion Frittata:

  • 1 pound asparagus, trimmed
  • 2 tablespoons extra-virgin olive oil
  • Kosher salt and freshly ground black pepper
  • 10 large eggs
  • 1 (5.2-ounce) package Garlic & Herb Boursin cheese
  • 1 tablespoon unsalted butter
  • 1 large sweet onion, such as Vidalia, thinly sliced (about 2½ cups)

How To Make (Directions)

  1. Preheat the oven to 425°F.
  2. Place the asparagus on a rimmed baking sheet and drizzle with 1 tablespoon of the olive oil. Season with a hefty pinch each of salt and pepper. Roast until the spears are cooked through but still have some bite, about 10 minutes (if the spears are quite fat, you may need to cook them longer). Remove from the oven and let cool slightly. Coarsely chop the asparagus into bite-size pieces.
  3. Reduce the oven temperature to 300°F.
  4. In a large bowl, whisk together the eggs, 3 tablespoons of the Boursin cheese, ½ teaspoon salt, and ½ teaspoon pepper (the Boursin will be pretty chunky; don’t worry about whisking it smooth).
  5. Heat a large cast-iron or another ovenproof skillet over medium heat. Add the butter and remaining 1 tablespoon olive oil to the pan. When the foaming subsides, add the onion. Cook, stirring occasionally, until the onion is translucent and soft, about 5 minutes. Add the asparagus and the egg mixture to the skillet and cook, undisturbed, for 1 minute.
  6. Transfer the skillet to the oven and bake until the eggs are just barely set and jiggle slightly when you shake the pan, 20 to 25 minutes. Remove the pan from the oven and use an offset spatula or a knife to release the frittata from the sides of the pan.
  7. Let the frittata cool for 5 minutes before transferring it to a large platter. Slice it into wedges and slather a tablespoon of the Boursin on each slice before serving.

#2 Roasted Broccoli and Cheddar Frittata

Here are another one of my favorite ways to make a frittata. While most people discard their broccoli stems, I peel and roast them to include right alongside the florets.

They add more broccoli flavor, not to mention an extra dose of healthy vitamins and minerals. I like to include a touch of red pepper flakes for some spice. Be sure to use a high-quality sharp cheddar cheese—the gooey topping will be all the more delicious for it.

Ingredients Roasted Broccoli and Cheddar Frittata:

  • 1½ pounds broccoli
  • 3 tablespoons olive oil
  • Kosher salt and freshly ground black pepper
  • 10 large eggs
  • 1 large onion, thinly sliced (about 2 cups)
  • ¼ teaspoon crushed red pepper flakes (optional)
  • ⅔ cup shredded sharp cheddar cheese

How To Make (Directions)

  1. Preheat the oven to 450°F.
  2. Cut the thick stems off the broccoli heads and set them aside. Divide the broccoli heads into small florets. Using a vegetable peeler, peel and discard the tough outer layer from the broccoli stems, then slice the stems into very thin coins.
  3. On a rimmed baking sheet, toss the sliced broccoli stems with 1 tablespoon of the olive oil, season with salt and black pepper, and spread out into an even layer. On a separate rimmed baking sheet, toss the broccoli florets with 1 tablespoon of the olive oil, season with salt and black pepper, and spread out into an even layer. Place both baking sheets in the oven and roast, stirring halfway through, until the broccoli is tender and browned in parts, about 15 minutes. Remove from the oven and let cool slightly.
  4. Reduce the oven temperature to 300°F.
  5. In a large bowl, whisk together the eggs, 1 teaspoon salt, and ½ teaspoon black pepper until smooth.
  6. Heat a large cast-iron or another ovenproof skillet over medium heat. Add the remaining 1 tablespoon olive oil and the onion. Cook, stirring occasionally, until the onion is very soft and slightly caramelized, about 15 minutes. Add the red pepper flakes, if using, and cook for 1 more minute. Add the roasted broccoli stems and florets, stir well, and spread the vegetables evenly in the skillet. Pour the egg mixture over the vegetables and use a spatula to spread it out evenly. Sprinkle the cheddar on top and cook, undisturbed, for 1 minute.
  7. Transfer the skillet to the oven. Bake until the eggs are just barely set and jiggle slightly when you shake the pan, 20 to 25 minutes. Remove the pan from the oven and use an offset spatula or a knife to release the frittata from the sides of the pan.
  8. Let the frittata cool for 5 minutes before transferring it to a large platter. Slice it into wedges and serve.