Mushroom Frittata delivers all satisfaction of quiche without time-consuming crust preparation. This protein-packed egg dish showcases earthy mushrooms, aromatic onions, and melted cheese in fluffy egg base that bakes to golden perfection. Perfect for breakfast, brunch, or light dinner, this versatile recipe works equally well served hot from oven or at room temperature. The absence of crust keeps it low-carb and gluten-free while letting mushroom flavor truly shine through.

Why You’ll Love This Recipe
- Easier than quiche with no crust to make or worry about
- Naturally low-carb and gluten-free for restricted diets
- Uses simple affordable ingredients found anywhere
- Makes impressive presentation for brunch entertaining
- Tastes delicious hot, warm, or at room temperature
Equipment Needed
- 10-inch oven-safe skillet or 9-inch pie dish
- Large mixing bowl
- Whisk
- Medium skillet for sautéing
- Measuring cups and spoons
- Spatula
Mushroom Frittata
- Total Time: 50 minutes
- Yield: 6 servings 1x
Description
Crustless mushroom frittata delivers all satisfaction of quiche without time-consuming crust. Earthy mushrooms, aromatic onions, and melted cheese in fluffy egg base create perfect low-carb gluten-free meal.
Ingredients
- 8 oz mushrooms, sliced (cremini, button, or mixed)
- 1 medium onion, diced
- 2 Tbsp butter or olive oil
- 3 cloves garlic, minced
- 8 large eggs
- ½ cup milk or cream
- 1 cup shredded cheese (Gruyere, Swiss, or cheddar)
- ½ tsp salt
- ¼ tsp black pepper
- ¼ tsp dried thyme
- 2 Tbsp fresh parsley, chopped
- Pinch of nutmeg (optional)
Instructions
1. Preheat oven to 375°F. Grease 10-inch oven-safe skillet or 9-inch pie dish with butter or cooking spray.
2. Heat butter or olive oil in medium skillet over medium-high heat. Add diced onion and cook 3-4 minutes until softened and translucent.
3. Add sliced mushrooms and minced garlic to skillet. Cook 6-8 minutes, stirring occasionally, until mushrooms release moisture and become golden brown. Season with pinch of salt and pepper.
4. In large bowl, whisk together eggs, milk, remaining salt, pepper, thyme, and nutmeg if using. Whisk until mixture is well combined and slightly frothy.
5. Stir in three-quarters of shredded cheese, reserving rest for topping. Add chopped parsley to egg mixture.
6. Spread cooked mushroom mixture evenly in prepared skillet or pie dish. Pour egg mixture over mushrooms, using fork to distribute vegetables evenly.
7. Sprinkle remaining cheese over top of frittata. This creates beautiful golden crust during baking.
8. Bake 25-30 minutes until eggs are completely set and top is golden brown. Frittata should puff slightly and knife inserted in center should come out clean.
Notes
Storage: Refrigerate covered up to 4 days. Reheat gently or enjoy cold.
Freezing: Wrap individual slices and freeze up to 2 months. Thaw overnight in refrigerator.
Variations: Add baby spinach last minute of cooking. Add diced bacon or ham for meat version. Use sun-dried tomatoes and mozzarella for Italian twist.
Pro Tips: Cook mushrooms until all moisture evaporates. Let frittata rest 5 minutes before slicing for neat cuts.
- Prep Time: 15 minutes
- Cook Time: 35 minutes
- Category: Breakfast
- Method: Baking
- Cuisine: French
Nutrition
- Serving Size: 1 wedge
- Calories: 195
- Sugar: 3g
- Sodium: 390mg
- Fat: 14g
- Saturated Fat: 7g
- Unsaturated Fat: 6g
- Trans Fat: 0g
- Carbohydrates: 6g
- Fiber: 1g
- Protein: 13g
- Cholesterol: 275mg
Ingredients
- 8 oz mushrooms, sliced (cremini, button, or mixed)
- 1 medium onion, diced
- 2 Tbsp butter or olive oil
- 3 cloves garlic, minced
- 8 large eggs
- ½ cup milk or cream
- 1 cup shredded cheese (Gruyere, Swiss, or cheddar)
- ½ tsp salt
- ¼ tsp black pepper
- ¼ tsp dried thyme
- 2 Tbsp fresh parsley, chopped
- Pinch of nutmeg (optional)
Ingredient Notes
Mix different mushroom varieties for complex flavor. Cremini add meatiness, shiitake bring umami depth, and oyster mushrooms contribute delicate texture.
Gruyere cheese creates classic French flavor but Swiss or sharp cheddar work beautifully too. Use cheese you enjoy eating since it’s prominent flavor in dish.
Fresh thyme tastes incredible if you have it. Use 1 teaspoon fresh thyme leaves instead of dried for brighter, more pronounced herb flavor.
Step-by-Step Instructions
Step 1
Preheat oven to 375°F. Grease 10-inch oven-safe skillet or 9-inch pie dish with butter or cooking spray.
Step 2
Heat butter or olive oil in medium skillet over medium-high heat. Add diced onion and cook 3-4 minutes until softened and translucent.
Step 3
Add sliced mushrooms and minced garlic to skillet. Cook 6-8 minutes, stirring occasionally, until mushrooms release moisture and become golden brown. Season with pinch of salt and pepper.
Step 4
In large bowl, whisk together eggs, milk, remaining salt, pepper, thyme, and nutmeg if using. Whisk until mixture is well combined and slightly frothy.
Step 5
Stir in three-quarters of shredded cheese, reserving rest for topping. Add chopped parsley to egg mixture.
Step 6
Spread cooked mushroom mixture evenly in prepared skillet or pie dish. Pour egg mixture over mushrooms, using fork to distribute vegetables evenly.
Step 7
Sprinkle remaining cheese over top of frittata. This creates beautiful golden crust during baking.
Step 8
Bake 25-30 minutes until eggs are completely set and top is golden brown. Frittata should puff slightly and knife inserted in center should come out clean.

Pro Tips & Cooking Hacks
- Cook mushrooms until golden to develop deep savory flavor
- Don’t rush mushroom cooking – let moisture evaporate completely
- Whisk eggs thoroughly for fluffy texture throughout
- Let frittata rest 5 minutes before slicing for neat cuts
- Use room temperature eggs for more even cooking
- Garnish with extra fresh herbs before serving
Tips & Variations
Add baby spinach to mushroom mixture during last minute of cooking. Spinach wilts quickly and adds color and nutrition.
Make it meaty by adding diced cooked bacon or ham. Sprinkle meat over mushroom layer before adding eggs.
Create Italian version with sun-dried tomatoes, fresh basil, and mozzarella cheese. This combination creates bright Mediterranean flavors.
Serving Suggestions
Serve for weekend brunch with mixed greens and fresh fruit. This creates balanced meal perfect for leisurely morning.
Cut into wedges and serve at room temperature for picnic or potluck. Frittata travels well and doesn’t require reheating.
Common Mistakes
- Not cooking mushrooms long enough, leaving them watery
- Adding mushrooms without sautéing first, creating soggy frittata
- Overbaking until eggs become rubbery instead of tender
- Using cold eggs straight from refrigerator
- Cutting before resting, causing frittata to fall apart
- Skipping cheese on top which creates less appealing appearance

What to Serve With
Pair with crusty bread and butter for simple satisfying meal. Bread soaks up any residual egg mixture beautifully.
Serve with roasted potatoes and tomato salad for hearty brunch spread. Combination covers all bases for complete meal.
Frequently Asked Questions
Can I make this without oven-safe skillet?
Yes! Start mushrooms in regular skillet, then transfer everything to greased pie dish before baking.
How do I prevent watery frittata?
Cook mushrooms until all moisture evaporates. Watery mushrooms release liquid during baking.
Can I use egg substitute?
Liquid egg substitute works but frittata may not puff as much. Use equivalent of 8 eggs according to package directions.
How long does leftover frittata keep?
Store covered in refrigerator up to 4 days. Reheat gently in microwave or enjoy cold.
Can I freeze mushroom frittata?
Yes! Wrap individual slices in plastic wrap and freeze up to 2 months. Thaw overnight in refrigerator before reheating.