Feta & Mushroom Brunch Squares Recipe
Feta & Mushroom Brunch Squares are the kind of dish that makes you look forward to brunch all week long. Imagine flaky puff pastry hugging a creamy, savory egg custard, packed with earthy mushrooms, sweet sautéed onions, and tangy crumbles of feta cheese. Parmesan adds a salty kick, and a sprinkle of fresh parsley on top makes every bite pop with color and freshness. Whether you’re hosting a gathering or just treating yourself to a cozy morning, these brunch squares are guaranteed to impress with their Mediterranean-inspired flair and irresistible flavor.

Ingredients You’ll Need
Each ingredient in Feta & Mushroom Brunch Squares has a delicious job to do, from adding texture and creaminess to boosting flavor and color. You don’t need a long list to make something truly special—just these simple, well-chosen ingredients.
- Olive oil: Adds a hint of richness and helps the onions and mushrooms sauté to perfection.
- Onion (1/2 small, finely chopped): Provides a gentle sweetness and depth that balances the umami mushrooms.
- Mushrooms (2 cups, sliced): The star of the show, bringing hearty texture and savory flavor.
- Dried thyme (1/2 teaspoon): Infuses the filling with subtle herbal notes for a Mediterranean touch.
- Salt (1/4 teaspoon): Enhances all the other flavors and keeps the dish perfectly seasoned.
- Black pepper (1/4 teaspoon): Adds a mild kick and balances the richness of the cheeses.
- Eggs (4 large): Create a luscious custard that binds all the ingredients together.
- Milk (1/2 cup): Makes the egg mixture super creamy and light.
- Feta cheese (1/3 cup, crumbled): Brings tangy flavor and creamy pockets throughout the squares.
- Parmesan cheese (1/4 cup, grated): Adds a salty, savory finish and helps the top brown beautifully.
- Puff pastry (1 sheet, thawed): The crisp, golden base that holds everything together—impossibly easy, always impressive.
- Fresh parsley (for garnish, optional): A sprinkle on top gives color and a burst of freshness.
How to Make Feta & Mushroom Brunch Squares
Step 1: Sauté the Vegetables
Begin by preheating your oven to 400°F. In a skillet over medium heat, warm the olive oil until it shimmers. Add the finely chopped onion and sauté for about two minutes, just until it’s soft and fragrant. Next, add the sliced mushrooms, dried thyme, salt, and pepper. Let everything cook together, stirring occasionally, until the mushrooms are tender and their liquid has evaporated—about 6 to 8 minutes. This step builds the flavorful foundation for your Feta & Mushroom Brunch Squares, so don’t rush it!
Step 2: Prepare the Egg and Cheese Mixture
While your mushroom mixture cools slightly, grab a medium bowl and whisk together the eggs and milk until smooth and fully combined. Stir in the crumbled feta and grated Parmesan cheese, making sure the cheeses are evenly distributed. This creamy, cheesy egg mixture will set into a custard as it bakes, holding everything together and infusing every bite with flavor.
Step 3: Assemble the Squares
Roll out your thawed puff pastry on a lightly floured surface just enough to fit your 8×8-inch baking dish or a similar-sized pan. Gently press the pastry into the parchment-lined dish, making sure it reaches into the corners for maximum coverage. Spread the cooled mushroom and onion mixture evenly over the pastry, then pour the egg and cheese mixture on top, letting it seep into every nook and cranny. This layering ensures every slice of Feta & Mushroom Brunch Squares is packed with deliciousness.
Step 4: Bake to Perfection
Slide your assembled dish into the preheated oven and bake for 25 to 30 minutes. You’re looking for a golden, puffed pastry crust and an egg filling that’s set in the center. The aroma will fill your kitchen and might just draw a crowd! Once baked, let the brunch squares cool for a few minutes before slicing—this makes them easier to serve and helps the flavors settle.
Step 5: Garnish and Serve
Just before serving, sprinkle the squares with freshly chopped parsley if you like. This simple touch adds a pretty pop of green and a bit of brightness that complements the creamy, savory filling. Now your Feta & Mushroom Brunch Squares are ready to steal the spotlight at your brunch table!
How to Serve Feta & Mushroom Brunch Squares

Garnishes
A scatter of fresh parsley or a few extra crumbles of feta cheese on top gives a burst of color and a hint of fresh flavor. You could also add a pinch of cracked black pepper or a drizzle of good olive oil for that extra-special touch.
Side Dishes
Pair Feta & Mushroom Brunch Squares with a crisp green salad tossed in a lemony vinaigrette, or serve with roasted tomatoes and breakfast potatoes for a heartier meal. Fresh fruit—think berries or sliced oranges—adds a sweet, juicy contrast that balances the savory richness of the squares.
Creative Ways to Present
Cut your brunch squares into mini finger-food sizes for a party platter, or serve larger portions alongside a bowl of herbed yogurt for dipping. For a brunch buffet, arrange the squares on a rustic wooden board with small signs labeling the dish, so everyone can admire your Mediterranean-inspired creation.
Make Ahead and Storage
Storing Leftovers
Keep any leftover Feta & Mushroom Brunch Squares in an airtight container in the refrigerator. They’ll stay fresh and delicious for up to three days, making them perfect for a quick breakfast or an easy lunch on the go.
Freezing
To freeze, let the squares cool completely, then wrap individual pieces tightly in plastic wrap and place them in a freezer-safe bag or container. They’ll keep well for up to two months. When you’re ready to enjoy, thaw overnight in the fridge or reheat directly from frozen (just add a couple extra minutes to the reheating time).
Reheating
Reheat your brunch squares in a 350°F oven for about 10 minutes, or until warmed through and the pastry is crisp again. You can also use the microwave for a quick fix, though the pastry may be a little softer. Either way, they’ll still taste fantastic!
FAQs
Can I use a different type Breakfast
Absolutely! While feta and Parmesan give classic Mediterranean flavor, you can substitute goat cheese, shredded mozzarella, or even a sharp cheddar if you prefer. Just keep in mind the flavor profile will change a bit, but the results will still be delicious.
What mushrooms work best in Feta & Mushroom Brunch Squares?
Cremini or white button mushrooms are perfect, but you can also use baby bellas or a combination of your favorites. For a deeper flavor, try adding a few chopped shiitake or oyster mushrooms to the mix.
Can I make these squares gluten-free?
Yes! Simply swap the puff pastry for a gluten-free variety, which is becoming more widely available. Double-check all your labels to ensure everything is gluten-free and you’re good to go.
Is it possible to prepare Feta & Mushroom Brunch Squares ahead of time?
Definitely. You can make the mushroom filling the night before and assemble everything in the morning, or bake the whole dish ahead and reheat gently before serving. It’s a wonderful option for easy entertaining.
Can I add extra vegetables to the filling?
Of course! Spinach, sun-dried tomatoes, or roasted red peppers all make great additions. Just be sure to sauté or drain any veggies with lots of moisture so the pastry stays crisp and the custard sets properly.
Final Thoughts
There’s something truly special about pulling a golden, fragrant pan of Feta & Mushroom Brunch Squares from the oven and sharing it with people you love. It’s the kind of recipe that brings warmth and good cheer to any table. I hope you’ll give it a try—your brunch game is about to get a major upgrade!
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Feta & Mushroom Brunch Squares Recipe
- Total Time: 45 minutes
- Yield: 6 squares 1x
- Diet: Vegetarian
Description
These Feta & Mushroom Brunch Squares combine the earthiness of sautéed mushrooms with the tangy richness of feta and Parmesan cheeses, all nestled in a flaky puff pastry crust. Perfect for a savory breakfast or light brunch, they’re easy to prepare and bake to golden perfection, offering a delightful Mediterranean-inspired flavor in every bite.
Ingredients
Vegetables and Herbs
- 1/2 small onion, finely chopped
- 2 cups mushrooms, sliced
- 1/2 teaspoon dried thyme
- 1/4 teaspoon salt
- 1/4 teaspoon black pepper
- Fresh parsley for garnish (optional)
Dairy and Eggs
- 4 large eggs
- 1/2 cup milk
- 1/3 cup crumbled feta cheese
- 1/4 cup grated Parmesan cheese
Other
- 1 tablespoon olive oil
- 1 sheet puff pastry, thawed
Instructions
- Preheat Oven: Preheat your oven to 400°F (200°C) to ensure it reaches the right temperature for baking the squares evenly.
- Sauté Vegetables: In a skillet over medium heat, heat the olive oil. Add the chopped onion and sauté for 2 minutes until slightly translucent. Add the sliced mushrooms, dried thyme, salt, and black pepper, cooking for 6 to 8 minutes until the mushrooms are tender and most of their liquid has evaporated. Remove from heat and let the mixture cool slightly.
- Prepare Egg Mixture: In a mixing bowl, whisk together the eggs and milk until well combined. Stir in the crumbled feta cheese and grated Parmesan cheese until evenly distributed.
- Prepare Puff Pastry Base: Lightly flour a surface and roll out the thawed puff pastry sheet if needed. Place it gently into an 8×8-inch (20×20 cm) baking dish lined with parchment paper, pressing it into the corners to fit evenly.
- Assemble Brunch Squares: Spread the cooled mushroom and onion mixture evenly over the puff pastry base. Pour the egg and cheese mixture over the top, distributing it so it fills the gaps and covers the mushrooms.
- Bake: Place the baking dish in the preheated oven and bake for 25 to 30 minutes. The squares are done when the center is set and the pastry is golden brown and puffed.
- Cool and Serve: Allow the brunch squares to cool slightly before slicing into six squares. Garnish with fresh parsley if desired and serve warm or at room temperature.
Notes
- Prepare the mushroom filling the night before to save time in the morning.
- For extra flavor, try adding chopped spinach or sun-dried tomatoes into the filling.
- These squares are versatile and can be served for brunch, lunch, or a light dinner.
- Make sure to allow the pastry to thaw fully before rolling and baking for best results.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Breakfast
- Method: Baking
- Cuisine: Mediterranean-Inspired
Nutrition
- Serving Size: 1 square
- Calories: 270
- Sugar: 2g
- Sodium: 330mg
- Fat: 19g
- Saturated Fat: 8g
- Unsaturated Fat: 9g
- Trans Fat: 0g
- Carbohydrates: 17g
- Fiber: 1g
- Protein: 9g
- Cholesterol: 115mg