Keto Crustless Zucchini Quiche Recipe tastes rich and cheesy with tender zucchini, perfect for low carb eaters who still crave comfort food, and it comes together in about 45 minutes total. It works well for busy folks who want a make-ahead breakfast, a quick lunch, or a light dinner that does not feel like “diet food.” I have baked some version of this quiche almost every Sunday for years, usually while drinking coffee and pretending my kitchen looks like a cooking show set.

Why Make This Keto Crustless Zucchini Quiche Recipe at Home

This crustless quiche gives you all the flavor of classic quiche without the carb-heavy crust. You get a golden, cheesy top, a custardy center, and plenty of vegetables in every slice.

You control the ingredients, which means no mystery starches or hidden sugars. You can tweak the cheese, add protein, or adjust the seasoning so it fits your taste and your macros.

“This Keto Crustless Zucchini Quiche Recipe tastes like brunch at a café, but with way fewer carbs and way more leftovers for the week. ★★★★★”

Ingredients You Need

Egg base

6 large eggs
1 cup heavy cream (or 3/4 cup heavy cream + 1/4 cup unsweetened almond milk to lighten it a bit)
1/2 teaspoon fine sea salt
1/4 teaspoon black pepper
1/4 teaspoon garlic powder
1/4 teaspoon onion powder
1/8 teaspoon ground nutmeg (optional, but it gives that classic quiche flavor)

Zucchini and mix-ins

2 medium zucchini, about 1 pound total, grated or very thinly sliced
1 tablespoon olive oil or avocado oil
2 cloves garlic, minced (or 1/2 teaspoon garlic powder if you want a pantry shortcut)
1/3 cup finely chopped onion or green onion
1/2 cup cooked bacon pieces or crumbled sausage (optional but highly recommended for extra flavor and fat)

Cheese

1 cup shredded mozzarella or Monterey Jack
1/2 cup shredded sharp cheddar or Gruyère
2 tablespoons grated Parmesan (adds a salty, nutty top)

You can use pre-shredded cheese from a bag if that fits your schedule. I prefer to shred a block of cheese because it melts smoother and usually skips extra starches. If you avoid cow dairy, you can try a mix of goat cheese crumbles and a lactose free hard cheese, but check labels for carbs.

Substitutions and notes

Swap zucchini with yellow squash in equal amounts.
Use half-and-half instead of heavy cream if you do not track carbs super tightly.
Add 1/2 teaspoon Italian seasoning or dried thyme if you want a more herb-forward flavor.
Use turkey bacon or chicken sausage if you prefer leaner protein, then add a little extra cheese for fat.

Equipment

9 inch pie dish or 9 inch round ceramic baking dish (light colored pans brown more gently)
Large skillet
Mixing bowl
Whisk
Box grater or food processor with shredding disc
Colander and clean kitchen towel or paper towels
Measuring cups and spoons

Tips & Mistakes

Squeeze the zucchini very well after salting so the quiche does not turn watery.
Salt the zucchini lightly and let it sit 10 minutes before squeezing to pull out more moisture.
Grease the pie dish generously so slices release cleanly.
Do not overbake; pull it when the center still jiggles slightly, because it finishes setting as it cools.
Let the quiche rest at least 10 to 15 minutes before slicing so it cuts neatly.
Use room temperature eggs and cream so the custard mixes smoothly.
Do not overload with too many mix-ins; keep total add-ins around 1 to 1 1/2 cups so it sets properly.
Taste the zucchini mixture before adding eggs and adjust salt so the final quiche does not taste bland.
Spread cheese evenly and keep some for the top so you get a nice golden crust.
Bake on the middle rack so the top browns without burning and the center cooks evenly.

How to Make Keto Crustless Zucchini Quiche Recipe

Prep the zucchini

Wash and dry the zucchini, then trim the ends.
Grate the zucchini on the large holes of a box grater or slice it very thinly.
Place the zucchini in a colander, sprinkle with a pinch of salt, and toss.
Let it sit 10 minutes, then squeeze handfuls over the sink and press in a clean towel until it feels quite dry.

Cook the veggies and protein

Heat the olive oil in a large skillet over medium heat.
Add the onion and cook 3 to 4 minutes until it softens and turns lightly golden.
Stir in the garlic and cook 30 seconds until fragrant.
Add the squeezed zucchini and cook 3 to 5 minutes, stirring, until it looks dry and some bits start to brown.
Stir in the cooked bacon or sausage, then turn off the heat and let the mixture cool slightly.

Mix the egg custard

Crack the eggs into a large mixing bowl.
Add the heavy cream, salt, pepper, garlic powder, onion powder, and nutmeg.
Whisk until the mixture looks smooth and slightly frothy.
Stir in most of the shredded cheese, keeping a small handful for the top.

Assemble the quiche

Preheat the oven to 350°F (175°C).
Grease a 9 inch pie dish with butter, oil, or nonstick spray.
Spread the zucchini and bacon mixture evenly in the dish.
Pour the egg and cheese mixture over the top, tilting the dish gently so it distributes evenly.
Sprinkle the remaining cheese and Parmesan over the surface.

Bake and cool

Place the pie dish on the middle rack of the oven.
Bake 30 to 40 minutes, until the edges puff and the center looks mostly set with a slight jiggle.
If the top browns too quickly, tent a piece of foil loosely over the dish.
Remove from the oven and let the quiche rest 10 to 15 minutes before slicing.
Slice into 6 to 8 wedges and serve warm, or cool completely for meal prep.

Variations I've Tried

I often swap the bacon with diced ham and add 1/2 cup of chopped spinach for a “green” version. I also like a Greek style twist with crumbled feta, sliced olives, and a little oregano instead of nutmeg. If I crave something more breakfast-forward, I use breakfast sausage, cheddar, and a pinch of smoked paprika.

You can keep it vegetarian and skip the meat, then add extra cheese and a handful of sautéed mushrooms. I also tried a jalapeño and pepper jack version that tasted amazing, especially with a dollop of sour cream on top. As long as you keep the egg to cream ratio steady and avoid too much moisture, this recipe stays very flexible.

How to Serve Keto Crustless Zucchini Quiche Recipe

Serve a warm slice with a simple green salad, sliced cucumbers, and cherry tomatoes for a light meal. Add a side of avocado or a small bowl of berries if you want more healthy fats and fiber. This quiche also works well at room temperature, so you can pack it in a lunch box with carrot sticks and a small container of ranch or yogurt dip.

For breakfast, pair it with black coffee, herbal tea, or a low carb smoothie. Kids often like it cut into small squares, almost like savory snack bites.

How to store

Fridge: Let the quiche cool completely, then cover the dish tightly or transfer slices to airtight containers and keep in the fridge for up to 4 days.
Freezer (whole): Wrap the cooled whole quiche in plastic wrap, then in foil, and freeze up to 2 months.
Freezer (slices): Wrap individual slices, place them in a freezer bag, and freeze up to 2 months for easy grab-and-go portions.
Reheating (oven): Reheat slices in a 325°F oven for 10 to 15 minutes until warm; this keeps the texture soft and not rubbery.
Reheating (microwave): Heat a slice on a microwave safe plate at 50 percent power in 30 second bursts until warm, and stop as soon as it heats through so it does not overcook.