There’s something so comforting about a homemade quiche, especially when it’s warm, cheesy, and packed with savory mushrooms. But what if we told you that you could have all that goodness without the fuss of a crust?

Enter this Crustless Mushroom and Swiss Quiche — your new go-to for a no-stress brunch, a light lunch, or even a cozy dinner. It’s low-carb, gluten-free, and incredibly flavorful. The mushrooms bring that earthy, umami depth, while Swiss cheese melts into the eggs to create a rich, custardy bite.

This is one of those recipes that feels fancy but is secretly very simple. You don’t need to be a seasoned cook to pull it off. And once you make it once, you’ll start imagining all the delicious variations you can try. Let’s break it down together.

Why You’ll Love This Recipe

This quiche has all the makings of a keeper. Whether you’re whipping it up for a lazy Sunday morning or prepping ahead for a busy week, here’s why it earns a spot in your regular recipe rotation.

Key Benefits

Easy to Make
No rolling out pastry dough, no blind baking — just a quick sauté, a whisk, and into the oven it goes.

Flavor-Packed
The combination of sautéed mushrooms, caramelized onions, and nutty Swiss cheese gives every bite rich flavor.

Customizable
Use what you have in the fridge. Add spinach, sun-dried tomatoes, or switch up the cheese. It’s a forgiving recipe that encourages creativity.

Meal Prep Friendly
Make it once, enjoy it all week. It reheats beautifully and works for breakfast, lunch, or a quick dinner.

Naturally Gluten-Free
Since there’s no crust, this quiche is naturally gluten-free without any need for special flours or substitutions.

Suitable For

Beginner Cooks
If you’re just getting started in the kitchen, this is a great confidence booster. Simple steps, big payoff.

Vegetarian Diets
No meat, all flavor. It’s hearty enough to satisfy without anything extra.

Low-Carb Lifestyles
If you’re watching your carbs or just want something a little lighter, this recipe is a smart choice.

Brunch Guests and Potlucks
It slices clean, looks lovely on a platter, and makes enough to serve a group. You can even double it in a casserole dish.

Ingredients for Crustless Mushroom and Swiss Quiche

You don’t need a long grocery list to make something impressive. In fact, you might already have most of these ingredients on hand.

Core Ingredients

Eggs (6 large)
The base of any quiche. They bind everything together and provide that creamy, custardy texture we love.

Mushrooms (1½ cups, sliced)
Use fresh mushrooms for best flavor. Cremini or white button mushrooms work great here.

Onion (1 small, finely chopped)
Adds subtle sweetness and depth once sautéed.

Swiss Cheese (1 cup, shredded)
Nutty, melty, and classic. You can also try Gruyère for a slightly sharper taste.

Milk (1 cup)
Whole milk gives the richest texture, but 2% or unsweetened plant-based milk like almond or oat will also work.

Olive Oil or Butter (1 tbsp)
For sautéing the veggies. Choose what suits your taste or pantry stock.

Salt, Pepper, and Thyme
These simple seasonings bring everything to life. Thyme is optional but adds a lovely herbal note.

Substitutions and Tips

• Cheese Swaps: Try cheddar, gouda, mozzarella, or even feta for a twist. Just be sure to shred or crumble it for even melting.

• Milk Options: Want a richer texture? Go for half-and-half or heavy cream. Dairy-free? Choose an unsweetened, neutral plant-based milk.

• Veggie Add-Ins: Baby spinach, sautéed bell peppers, sun-dried tomatoes, or even leftover roasted veggies all make great additions.

• Spice It Up: A pinch of red pepper flakes or a dash of hot sauce in the egg mixture can add subtle heat.

Pro Tip: Avoid watery quiche by cooking mushrooms thoroughly. Let them brown and release their moisture before adding them to the mix.

Best Mushrooms for Crustless Mushroom and Swiss Quiche

Mushrooms are the star of this recipe, so choosing the right kind makes a big difference.

Cremini (Baby Bella)
These are our top pick. They’re meatier and more flavorful than basic white mushrooms, but still cook quickly and evenly.

White Button Mushrooms
Milder in taste but still a solid choice, especially if you’re feeding picky eaters.

Portobello Mushrooms
Chopped finely, these give an even deeper, earthier flavor. They’re great if you want a more robust, savory bite.

Tips for Cooking Mushrooms

• Always sauté mushrooms until they’re golden and dry — no soggy bits allowed.

• Don’t overcrowd the pan. Give them space to brown.

• Season them lightly as they cook to boost flavor.

Kitchen Tools You’ll Need

No fancy equipment needed here. Just the basics you already have in your kitchen.

Must-Have Tools

9-inch Pie Dish or Quiche Pan
This is the perfect size for even baking and easy slicing.

Skillet
For sautéing your mushrooms and onions. A nonstick or stainless steel skillet works well.

Mixing Bowl
To whisk up your eggs and milk.

Whisk
Essential for getting that egg mixture smooth and well-combined.

Oven
You’ll bake the quiche at 375°F (190°C) until golden and set.

Nice-to-Have Tools

Silicone Spatula
Great for scraping every bit of goodness out of the bowl.

Mandoline Slicer
If you want paper-thin mushrooms or onions.

Cheese Grater
Grate your own cheese for better melt and flavor — pre-shredded often contains anti-caking agents that don’t melt as smoothly.

How to Make Crustless Mushroom and Swiss Quiche

Making this crustless mushroom and Swiss quiche is as straightforward as it gets. There’s no crust to roll, no dough to chill—just real ingredients and simple steps that come together in one delicious, savory bake. Think of it as a cozy, homemade hug in the form of food. Let’s walk through it, step by step.

Step 1: Preheat and Prep

Before anything else, go ahead and preheat your oven to 375°F (190°C). This gives it enough time to reach the right temperature while you prep the other ingredients.

Next, grease a 9-inch pie dish or quiche pan with butter, olive oil, or nonstick spray. This step keeps your quiche from sticking and makes cleanup a breeze.

Pro tip: If you’re doubling the recipe or adding extra veggies, consider using a deeper dish or a small casserole dish to keep things from overflowing.

Step 2: Sauté Mushrooms and Onions

This is where the magic starts. In a medium skillet, heat 1 tablespoon of olive oil or butter over medium heat.

• Add your chopped onion and sauté for about 3 to 4 minutes, until it’s translucent and soft.

• Then toss in your sliced mushrooms. Cook these for another 5 to 6 minutes, stirring occasionally, until they’ve released their moisture and started to brown.

Take your time here—this step builds the foundation of flavor. When the mushrooms look golden and smell amazing, remove the skillet from heat and let the mixture cool slightly.

Step 3: Mix the Egg Custard

While the veggies cool down, it’s time to whisk together the egg mixture.

In a large mixing bowl, combine:

• 6 large eggs

• 1 cup of milk (whole, 2%, or unsweetened plant-based)

• ½ teaspoon of salt

• ¼ teaspoon of black pepper

• ¼ teaspoon of dried thyme (optional, but highly recommended for that subtle herbaceous note)

Whisk until the eggs and milk are fully combined and the mixture is light and frothy.

Want to add a little zing? Stir in 1 teaspoon of Dijon mustard. It’s a small touch that adds a layer of tangy depth that pairs beautifully with Swiss cheese.

Step 4: Assemble the Quiche

Now for the fun part—putting it all together.

1. Evenly spread the sautéed mushrooms and onions across the bottom of your greased dish.

2. Sprinkle the shredded Swiss cheese over the top.

3. Carefully pour the egg mixture over everything. You can use the back of a spoon or a spatula to gently nudge the filling around if needed to make sure it’s evenly distributed.

You’ll notice it already looks beautiful and smells incredible—even before it hits the oven.

Step 5: Bake

Slide your dish into the preheated oven and bake for 30 to 35 minutes, or until the quiche is set in the center and lightly golden on top.

How to tell when it’s ready? Insert a knife into the center—if it comes out clean, you’re good to go. The top should have a gentle puff, and the edges might be just starting to turn golden.

Once baked, remove from the oven and let it cool for 5 to 10 minutes before slicing. This helps the custard finish setting and makes slicing much easier.

Tips for Success

Even though this quiche is easy, a few smart tricks can take it from good to great.

• Always sauté your mushrooms first. Skipping this step can lead to a watery quiche.

• Use freshly grated cheese when possible. It melts better and gives a creamier texture.

• Let it rest after baking. It’ll slice cleaner and hold together better once slightly cooled.

• Don’t overbake. Keep a close eye on the oven after the 30-minute mark—overcooked eggs can become rubbery.

• Make it your own. Add-ins like chopped spinach, fresh herbs, or even a bit of crumbled cooked bacon can add even more personality.

How to Store Crustless Mushroom and Swiss Quiche

This quiche keeps surprisingly well, which makes it perfect for meal prepping or saving leftovers.

At Room Temperature

Once baked, your quiche can sit out for up to 2 hours at room temperature. This makes it ideal for brunch spreads or buffets.

In the Refrigerator

Allow the quiche to cool completely, then cover tightly with plastic wrap or transfer to an airtight container. It will keep in the fridge for up to 4 days.

To reheat, you can microwave individual slices or warm the whole dish in a 300°F oven for 10–15 minutes.

Freezing Tips

Yes, you can absolutely freeze it. Here’s how:

• Let the quiche cool completely.

• Wrap the whole quiche—or individual slices—in plastic wrap, then in foil.

• Freeze for up to 2 months.

To reheat, thaw overnight in the refrigerator and warm in the oven at 325°F until heated through.

Frequently Asked Questions (FAQs)

Can I make this quiche ahead of time?

Absolutely. You can prepare the entire quiche the night before, refrigerate it unbaked, and pop it in the oven the next morning. Just add an extra 5–10 minutes to the baking time since it will be cold.

Alternatively, bake it fully, let it cool, and refrigerate. Reheat as needed.

Can I use a different cheese?

Of course. Swiss adds that nutty, mellow flavor, but Gruyère, cheddar, gouda, or even feta can all work. Feel free to get creative based on what you have.

How do I keep my quiche from turning out watery?

The key is to sauté your mushrooms until all the moisture cooks off. You can also avoid adding raw high-water-content veggies unless they’ve been cooked and drained.

Can I add meat?

Yes! Cooked and crumbled bacon, ham, or breakfast sausage make excellent additions. Just make sure the meat is cooked through and drained before adding it to the quiche.

Related Recipes

If you loved this Crustless Mushroom and Swiss Quiche, you might enjoy these easy and flavorful recipes:

• Cottage Cheese Spinach Crustless Quiche – A protein-packed twist with cottage cheese and greens.

• Mushroom and Feta Crustless Quiche – Rich and tangy with a Mediterranean touch.

• Creamy Mushroom and Asparagus Chicken Penne – For mushroom lovers who want a creamy, hearty dinner.

• Spinach Egg and Cheese Delight – A breakfast casserole that’s family-friendly and low-carb.

• Creamy Mushroom Soup – A cozy soup perfect for pairing with a slice of this quiche.

Conclusion

This crustless mushroom and Swiss quiche is a true gem—simple to make, endlessly adaptable, and packed with comforting flavor. Whether you’re feeding your family, prepping lunches for the week, or hosting a weekend brunch, this recipe delivers every time.

And once you’ve mastered the basic version, don’t be afraid to play with new flavor combos. That’s the beauty of a good quiche—it welcomes whatever you have on hand. Give it a try, and let your kitchen become your canvas

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