Agrodolce Onion Frittata with Balsamic Vinegar

This agrodolce onion frittata is two recipes in one. You cook down a large amount of red onions ahead of time and use some for the frittata, and the rest for something else! That being said, here at Gustiamo we’re on a two frittata per week schedule. We’ll probably end up using up all those balsamic-infused onions in a frittata at some point. Let’s be honest, we all agree that nothing enhances the egg-y flavors of frittata better than an agrodolce pairing.


SERVES: 4-5 people
TIME: 40 minutes



  1. In a pan, heat EVOO over low heat. Add the onions and cook until very soft, stirring from time to time (about 45 minutes).
  2. Add the Balsamic Saba 3 and season with salt and pepper. Stir until the liquid is reduced, another 5 minutes or so.
  3. Remove from the heat, and allow to cool slightly*.
  4. Meanwhile, beat the eggs in a large bowl. Stir in the grated cheese, herbs, and about half the agrodolce onions, reserving the remaining for another use. Season with salt and pepper.
  5. Grease a cast-iron skillet with EVOO, then pour the egg mixture into the skillet.
  6. Cook in a preheated oven at 350°F for about 25 minutes.
  7. Finish under the broiler for 1 to 2 minutes, watching very carefully to make sure the top doesn’t burn.
  8. Remove from the oven, and allow to cool for at least 5 minutes.
  9. Serve warm, finishing each slice of frittata with a few drops of Traditional Balsamic vinegar.

*You can serve Agrodolce onions also as an appetizer or a side dish.

Watch the video for our frittata instructions: