This easy spinach, mushroom, and feta frittata delivers savory, rustic comfort in every slice. With tender cremini mushrooms, wilted garden spinach, aromatic garlic, and pockets of salty feta cheese, this versatile dish transitions effortlessly from a relaxed weekend brunch to a quick, protein-packed weekday lunch or dinner. Because it requires only a handful of wholesome pantry staples and cooks entirely in one oven-safe skillet, cleanup is minimal and straightforward.
Prep time: 15 minutes
Cook time: 25 minutes
Total time: 40 minutes
Servings: 4 to 6 servings
Ingredients
- 8 large eggs
- 60 ml (1/4 cup) whole milk or unsweetened plain dairy-free milk
- 15 ml (1 tablespoon) extra virgin olive oil
- 225 g (8 oz) cremini or button mushrooms, thinly sliced
- 150 g (about 4 packed cups) fresh baby spinach, roughly chopped
- 2 cloves garlic, finely minced
- 1/4 teaspoon sea salt (feta adds natural salinity)
- 1/4 teaspoon freshly cracked black pepper
- 1/4 teaspoon dried oregano or dried thyme
- 75 g (about 1/2 cup) crumbled feta cheese
- 15 g (2 tablespoons) fresh flat-leaf parsley, finely chopped (optional, for garnish)
Instructions
- Preheat your oven to 190°C (375°F) with a rack arranged in the middle position.
- In a medium mixing bowl, whisk together the eggs, milk, salt, black pepper, and dried oregano until completely smooth and lightly frothy. Set aside.
- Heat the olive oil in a 25 cm (10-inch) oven-safe, nonstick or well-seasoned cast-iron skillet over medium heat.
- Add the sliced mushrooms and cook undisturbed for 3 to 4 minutes until they begin to brown. Stir and continue cooking for another 2 to 3 minutes until tender and moisture has evaporated.
- Add the minced garlic and cook for about 30 seconds until fragrant, stirring constantly to prevent burning.
- Add the chopped baby spinach in two batches, tossing gently until completely wilted, about 2 minutes. Spread the sautéed vegetables evenly across the bottom of the skillet.
- Pour the whisked egg mixture evenly over the vegetables. Gently tilt the pan if necessary to distribute the liquid evenly.
- Sprinkle the crumbled feta cheese evenly across the top. Allow the frittata to cook undisturbed on the stovetop over medium-low heat for 2 to 3 minutes, until the edges begin to set slightly.
- Carefully transfer the skillet to the preheated oven. Bake for 14 to 18 minutes, or until the center is just set and does not jiggle when the pan is gently shaken. For a lightly browned top, switch on the broiler for the final 1 to 2 minutes.
- Remove the skillet from the oven using an oven mitt (the handle will be extremely hot). Let the frittata cool in the pan for 5 minutes before slicing. Garnish with chopped fresh parsley and serve warm or at room temperature.
Tips for consistent results
- Evaporate vegetable moisture: Both mushrooms and spinach release significant moisture during cooking. Sauté them thoroughly before pouring in the eggs; excess liquid can make the center of the frittata watery or spongy.
- Mind the pan handle: Always use an oven-safe skillet. If using cast iron, ensure it is well-seasoned or lightly oiled up the sides to prevent sticking. Always keep a silicone handle cover or cloth nearby after removing it from the oven.
- Avoid overcooking: Eggs continue to cook from residual heat after leaving the oven. Pull the frittata out as soon as the center is barely firm to preserve a tender, custardy crumb rather than a rubbery texture.
Food safety
- Cook the egg mixture until it reaches an internal temperature of at least 71°C (160°F), ensuring the center is completely coagulated and safe to eat.
- Do not leave the cooked frittata at room temperature for longer than 2 hours. Refrigerate leftovers promptly in shallow, airtight containers to cool them quickly.
- When reheating leftovers, ensure they are heated through to steaming hot (at least 74°C / 165°F) before consuming.
Variations
- Dairy-free option: Substitute the whole milk with unsweetened oat or almond milk, and replace the feta with a plant-based crumbly cheese or 2 tablespoons of nutritional yeast folded into the egg batter.
- Added protein: Fold in 60 g of cooked shredded chicken breast, diced smoked salmon, or lean turkey bacon along with the sautéed vegetables.
- Vegetable swaps: Add halved cherry tomatoes, thinly sliced bell peppers, or steamed chopped broccoli florets in place of or alongside the mushrooms.
Storage
Store cooled leftover slices in an airtight container in the refrigerator for up to 4 days. Reheat individual slices in a toaster oven or skillet over medium-low heat until warmed through, or microwave in 30-second bursts on 70% power to prevent the eggs from becoming tough. Slices can also be individually wrapped and frozen for up to 2 months; thaw overnight in the refrigerator before gently reheating.
Frequently Asked Questions
Can I make this frittata ahead of time for weekly meal prep?
Yes, frittatas are exceptionally meal-prep friendly. Slice the cooled frittata into single servings, place them between parchment squares inside an airtight meal container, and keep them refrigerated for up to 4 days for grab-and-go morning meals.
Can I use frozen spinach instead of fresh?
You can use frozen spinach, but ensure it is completely thawed and thoroughly squeezed dry in a clean kitchen towel before adding it to the pan. Any lingering water will compromise the texture of your eggs.
What should I serve alongside this dish?
This frittata pairs nicely with a crisp green salad dressed in lemon vinaigrette, roasted breakfast potatoes, or a slice of warm wholegrain sourdough toast.
Nutritious cooking fits best into daily life when meals remain simple, flexible, and satisfying. Savor this vibrant frittata warm from the oven or packed chilled for a busy afternoon lunch.