Baked Caramelized Mushroom, Onion, Spinach, and Swiss Cheese Frittata

After we’d made strombolis over the weekend with Yahnni, we were left with a bunch of ingredients that begged to be used.  Since I didn’t want to let leftover browned crumbled Italian sausage, cubed Jarlsberg swiss cheese, or sliced cremini mushrooms go to waste, I adapted the following recipe to use them and it turned out very nicely.  Note that I used a greased nonstick deep dish pie pan instead of a tart pan; it worked just as well. In the future I might add sliced parboiled white potatoes to the frittata, shooting for a Torta Espanola vibe. We’ll see.

Baked Caramelized Mushroom, Onion and Swiss Frittata

Baked Caramelized Mushroom, Onion, Spinach, and Swiss Cheese Frittata

Recipe from For the Love of Cooking.net

INGREDIENTS

1 tbsp of olive oil
1/2 sweet yellow onion, chopped
8 oz button mushrooms, sliced
2 cups of baby spinach
1/4 cup Swiss cheese, diced (I used Jarlsberg)
8 eggs
2-3 tbsp milk
Sea salt and freshly cracked pepper, to taste

DIRECTIONS

Preheat the oven to 350 degrees. Coat a tart pan with cooking spray.

Heat the olive oil in a large skillet over medium high heat. Add the onions and mushrooms then cook stirring often until caramelized, about 15-20 minutes. Add the spinach to the skillet then season with sea salt and freshly cracked pepper, to taste. Toss until well combined.

Place some of the mushroom & onion mixture and Swiss cheese into the bottom of the tart pan. Combine the eggs with the milk then season with sea salt and freshly cracked pepper, to taste. Whisk the eggs until they are mixed thoroughly.

Pour the egg mixture into the tart pan then add the remaining onion mixture and Swiss cheese to the top.

Place into the oven and bake for 20-25 minutes, or until a tester inserted in the center comes out clean. Let the frittata cool for a few minutes before slicing and serving. Enjoy.