Pin it
This rich, indulgent Keto Caramelized Onion and Gruyère Quiche turns ordinary breakfast into a fancy treat without loading up on carbs. The nutty almond flour base perfectly supports the creamy filling packed with sweet slow-cooked onions and gooey melted Gruyère.
I came up with this quiche when I needed to feed a mix of friends with different food needs. My keto buddies were so happy to have something filling they could actually eat, and everyone else was too busy enjoying the amazing flavors to care it wasn't full of carbs. Now I can't host without making it.
Ingredients
- Almond flour: Gives a tasty nutty base while keeping carbs down; grab the blanched kind for the best texture
- Garlic powder: Adds a punch of flavor to the crust that works great with the filling
- Salt: Brings out all the other tasty elements without standing out
- Butter: Holds the crust together and makes it rich; pick unsalted so you can control the taste better
- Butter: For cooking down the onions; makes everything smooth and delicious
- Onion: The hero that turns sweet and golden when cooked slowly; yellow or sweet varieties work best
- Gruyère cheese: Brings fancy nutty flavor that makes this quiche special; try aged Gruyère for stronger taste
- Eggs: Create the smooth base that holds everything in place; fresh-from-the-farm eggs really do taste better
- Heavy cream: Makes everything velvety without needing flour to thicken it
- Salt and pepper: Pull together and highlight the natural goodness of everything else
Step-by-Step Instructions
- Prepare the Crust:
- Mix almond flour, garlic powder, and salt in a bowl, stirring well to spread the spices evenly. Add the melted butter and stir until you get something that looks like wet sand. It'll seem a bit loose but don't worry. Press this mixture into a 9-inch pie dish, pushing firmly on the bottom and up the sides to make it about ¼-inch thick all around. You can use a flat-bottomed glass to pack down the bottom layer. Make the edges look nice with your fingers and poke the bottom several times with a fork so it doesn't bubble up. Bake at 325°F for 10-12 minutes until the edges start looking golden.
- Caramelize the Onions:
- Heat butter in a big pan over medium-low heat until it bubbles a bit. Toss in your thinly sliced onions, spreading them out. Add a tiny bit of salt to help pull out moisture and stir often for the first 5 minutes. Turn the heat down slightly and keep cooking for 15-20 minutes, stirring now and then for even cooking. You'll watch them change from white to gold to deep amber. They're done when they're super soft and deeply colored but not burnt or crispy. Taking your time here is worth it—this slow cooking is what makes this quiche taste amazing.
- Assemble the Quiche:
- Spread your cooked onions all over the bottom of the cooled crust, using a spoon to make sure they're evenly distributed so every bite has some. Scatter half the shredded Gruyère on top, letting some fall between the onion pieces. In another bowl, beat eggs and heavy cream together until they're well mixed and a bit foamy, then add salt and pepper. Carefully pour this mixture over the onions and cheese, filling the crust almost to the top. Sprinkle the rest of the Gruyère on top, which will create a gorgeous golden crust as it bakes.
- Bake to Perfection:
- Put the quiche on the middle shelf of your oven and bake at 325°F for 35-40 minutes. It's done when the edges are set but the center still jiggles just a tiny bit when you gently shake it. The top should look golden brown with melted, bubbly cheese. Take it out and let it sit for at least 15 minutes before cutting. This waiting step matters—it lets everything firm up so you get nice clean slices.
Pin it
Those caramelized onions really make this dish special. I found out how amazing they can be by accident when I left some cooking too long once. What I thought was a mistake turned out to be food magic—they got this amazing sweet depth that works perfectly with the nutty Gruyère. Now my husband asks for this quiche instead of cake on his birthday!
Storage and Make-Ahead Tips
This quiche keeps really well in the fridge for up to 4 days. Just wrap it tightly with plastic wrap after it's completely cool. When you want to eat it again, let slices come to room temperature first, then warm them in a 300°F oven for about 10 minutes. You can also freeze the whole quiche or individual pieces. Wrap them up tight in plastic, then foil, and freeze for up to 3 months. Thaw in the fridge overnight before reheating. The crust might not be quite as crisp after freezing, but it'll still taste fantastic.
Pin it
Perfect Pairings
This quiche really shines as the star of a keto-friendly brunch with the right sides. Try serving it with a simple arugula salad with just lemon juice and olive oil to cut through the richness. If you've got non-keto friends over, you can put out some nice bread for them too. It works just as well for dinner alongside some roasted asparagus or brussels sprouts. And it tastes great with a glass of dry white wine like Sauvignon Blanc or a light Pinot Noir that goes well with the sweet onions and cheese.
Customization Options
While this recipe tastes amazing as is, you can totally make it your own. Try swapping half the Gruyère for sharp cheddar or fontina if you want. Throw in some cooked bacon bits or pancetta for a smoky taste. Mix in fresh herbs like thyme or chives for brightness. You can also add sautéed mushrooms, spinach, or roasted red peppers for more veggies. Just make sure to cook out any extra water from the vegetables first so your quiche doesn't get soggy.
Frequently Asked Questions
- → How do I get the onions caramelized right?
Keep the burner on medium-low, stir often, and be patient. Let them slowly release their sugars for that amazing depth of flavor.
- → Is it possible to swap the almond crust?
You can! Try coconut flour or cauliflower-based crusts, but expect slight changes in taste and texture.
- → How do I know when the quiche is done?
It's ready when the center is firm yet slightly wobbly. Let it cool for 15 minutes—it slices better that way.
- → Can I prep it in advance?
Absolutely! It stays fresh in the fridge for up to 3 days. Heat in the oven when you're ready to serve.
- → What if I want to use a different cheese?
Go ahead and swap Gruyére with Swiss or sharp cheddar if you prefer a twist on the flavors.
- → Can I freeze the quiche?
Totally! Cool it down, wrap it in plastic and foil, then freeze. Thaw it and bake until warm when you're ready to eat.