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–+ servings

Caramelized Onion and Mushroom Frittata

The glorious combination of butter, onions, mushrooms, thyme and white wine in a Sunday brunch frittata.
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Prep Time: 25 minutes
Cook Time: 20 minutes
Total Time: 45 minutes
Course: Breakfast, Brunch
Cuisine: American, French
Keyword: frittata, mushrooms, thyme, white wine
Servings: 8
Calories: 240kcal

Ingredients

  • 1 tbsp extra virgin olive oil
  • 2 tbsp butter
  • 1 small yellow onion, cut in half and sliced
  • salt and pepper
  • 2 cups assorted chopped fresh mushrooms
  • 1 tsp fresh thyme
  • 1/4 cup white wine
  • 8 eggs
  • 2/3 cup heavy cream
  • 1 tbsp Dijon mustard
  • 1/4 tsp baking powder
  • 1/2 cup swiss cheese, shredded
  • 3/4 cup Gruyere cheese, shredded

Instructions

  • Preheat oven to 350°.
  • Heat an oven-safe medium non-stick saute pan over medium-low heat for 1 minute. Add 1 tbsp olive oil and 1 tbsp of the butter. Once melted add sliced onion, stir and season generously with salt and pepper. Leave alone for 7-10 minutes. Once the onions start to caramelize, stir them around to ensure even browning, about 15 minutes total.
  • Meanwhile, whisk together eggs, cream, Dijon and baking powder. Season with salt and pepper and set aside.
  • Raise heat to medium and add 1 tbsp butter to pan. Allow to melt and add the mushrooms. Stir to coat and combine with the onions. Continue to cool for about 4 minutes until mushrooms are beginning to soften but are still al dente.
  • Raise the heat to medium high. Wait 1 minute and then add white wine. Allow to simmer down until most of the liquid has evaporated, about 3 minutes. Add the fresh thyme (save a pinch for finishing). Get a good whiff of the pan now....mmmmmm.
  • Reduce heat to medium and pour egg mixture over the mushrooms. Stir gently to ensure everything is evenly distributed. Top with swiss and gruyere cheese, shimming the pan to allow the cheese to sink. Finish with the remaining pinch of fresh thyme and allow to cook on the stove for about 4 minutes until edges are set.
  • Transfer to oven and bake at 350° for 20 minutes or until set. Allow to rest 10 minutes before slicing and serving.

Notes

There is nothing better than the aroma of onions, mushrooms and fresh thyme cooking in butter and white wine.
This fancy frittata is perfect for Easter Sunday brunch.  Serve with a fancy green salad on the side.
Check out my other frittata recipes here:  https://onceuponafrittata.com/food/recipe-collections/

Nutrition

Serving: 1slice | Calories: 240kcal | Carbohydrates: 6g | Protein: 13g | Fat: 18g | Saturated Fat: 9g | Trans Fat: 1g | Cholesterol: 204mg | Sodium: 167mg | Potassium: 288mg | Fiber: 2g | Sugar: 2g | Vitamin A: 667IU | Vitamin C: 2mg | Calcium: 232mg | Iron: 1mg
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