Pepper, Onion, Mushroom and Feta Frittata
on Jan 25, 2017, Updated Jan 24, 2025
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If you've got a half dozen eggs and some random ingredients, you've got a frittata.

There is both a lot and not all that much to say about frittatas.
I’ve made a lot of them in my day. They are flexible and delicious and one of the easiest and fastest ways to use up leftovers that I know of. They can be served as appetizers, snacks, and a light main course. Hot, warm, or cold. Morning, noon, and night. All hail the flexible frittata.
This one features shiitake mushrooms, bell peppers, feta, and onions. Also thyme. But, as with all frittatas, these are just suggestions.
More Frittatas
Frittatas are endlessly customizable with whatever you have in the fridge. Learn more about what can go into them, and get essential frittata-making tips at How to Make a Frittata.
Try the Swiss Chard Frittata with ribbons of greens running around. You could use any greens in this instead of the chard, like kale or finely slivered collard greens.
The Spinach Frittata with Bacon and Goat Cheese has a great array of flavors and stars bacon lardons.
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Pin ItPepper, Onion, Mushroom and Feta Frittata
Ingredients
- 2 tablespoons olive oil divided
- 1 tablespoon butter
- 1 small red onion halved and thinly sliced
- 5 ounces sliced shiitake or other mushrooms
- ½ cup minced red, yellow or orange bell pepper or a combination
- 1 teaspoon minced fresh thyme leaves
- Kosher salt and freshly ground black pepper to taste
- 8 large eggs
- ¼ cup crumbled feta
Instructions
- Preheat the broiler. Heat an 8 to 10-inch skillet over medium high heat. Add 1 tablespoon of the oil and the butter. Add the onions, and sauté for about 3 minutes until they have started to become tender, then add the mushrooms and sauté for 5 minutes, until fairly tender. Add the peppers and sauté for 2 more minutes until they start to become tender. Stir in the thyme.
- Beat the eggs, add them to the pan, stirring frequently for two minutes. Lower the heat to medium low and cook for 2 to 3 minutes until the eggs are set on the bottom. Sprinkle the top with the feta.
- Transfer to the broiler. Broil for 1 to 2 minutes until the top is set and the frittata is lightly puffed. Serve hot or at room temperature.
When do you add the feta????
so sorry – it’s there now!