Colorful Oven-Baked Vegetable Frittata

Sunday mornings at my neighbor's place always ended the same way: her standing at the stove with a cup of coffee, somehow turning whatever vegetables lingered in her crisper drawer into something that made everyone gather around the kitchen island. That's when I first watched her make a frittata, and honestly, it seemed like she was just winging it. Eggs, cheese, whatever looked good that day, straight into a hot skillet and then into the oven. No fuss, no fancy footwork, just real food that tasted like someone actually cared.

I made this for a friend who'd just moved into her first apartment, and she stood there watching the frittata puff up in the oven like it was the most magical thing she'd ever seen. When we pulled it out, golden and still slightly jiggly in the center, she actually teared up a little. Turns out her mom used to make something similar, and she'd forgotten how good it tasted. We ate half of it right there, standing in her mostly empty kitchen, and suddenly the place felt like home.

Ingredients

• Broccoli florets: They hold their shape better when you chop them smaller and add them first to the pan, giving them time to soften without becoming mushy.
• Red bell pepper: The sweetness balances the earthiness of everything else, and the color makes the whole thing look like you planned it.
• Zucchini: Slice it thin so it releases its moisture into the eggs and doesn't stay watery or tough.
• Cherry tomatoes: Halve them so they don't roll around and they distribute their brightness evenly throughout.
• Red onion: Thin slices mellow out as they cook and add a subtle sweetness that ties the vegetables together.
• Large eggs: Room temperature eggs whisk more smoothly and create a creamier texture, so pull them from the fridge a few minutes early.
• Whole milk: It makes the eggs custard-like and tender, but if you're vegan, oat milk works just as well and maybe even better.
• Cheddar cheese: Sharp cheddar adds more flavor than mild, but feta gives you a tangy edge and goat cheese brings unexpected sophistication.
• Fresh parsley: Scattered on top at the end, it tastes bright, but dried works if that's what you have and you won't judge yourself for it.
• Salt, pepper, oregano: These three are the backbone, and oregano especially wakes up the whole dish and reminds you this is Italian.
• Olive oil: Good enough to taste but not so fancy you're afraid to cook with it; medium heat is your friend here.

Instructions

Heat your oven and get your skillet ready:

Set the oven to 375°F and let it warm while you work. Use a 10-inch oven-safe skillet, which is non-negotiable because it needs to survive the oven without the handle melting or the pan warping.

Start the vegetables in warm oil:

Pour olive oil into the skillet over medium heat, then add broccoli, bell pepper, zucchini, and onion. You'll hear the initial sizzle soften into a gentle sizzle, which means you're at the right temperature. Cook for 4 to 5 minutes, stirring occasionally, until the vegetables are starting to soften but still have some personality.

Add the tomatoes and build flavor:

Stir in the halved cherry tomatoes and let them warm through for about a minute. This is when the whole skillet starts smelling incredible, and you'll know you're close to the next step.

Whisk your eggs into something silky:

In a separate bowl, whisk together eggs, milk, salt, pepper, oregano, and parsley until the mixture is uniform and creamy. Don't overthink this, just make sure the yolks are fully incorporated and there are no streaks of egg white hiding at the bottom.

Pour and top:

Pour the egg mixture evenly over the vegetables in the skillet, making sure it fills in the gaps. Sprinkle cheese across the top so you get some in every bite, but don't go overboard or it'll brown too much before the center sets.

Start on the stovetop to set the edges:

Leave the skillet on medium heat for 2 to 3 minutes until you see the edges starting to firm up around the sides. This head start helps the frittata cook evenly and prevents the bottom from getting too brown.

Finish in the oven:

Transfer the skillet to the preheated oven and bake for 15 to 18 minutes until the center is set but still has the tiniest bit of jiggle when you gently shake the pan. The top should be golden and slightly puffed, like it's proud of itself.

Rest and serve:

Let it cool for 5 minutes so it holds together when you slice it. Serve it warm, at room temperature, or even cold the next day, and people will think you spent hours on this.

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There's a moment when a frittata comes out of the oven and the kitchen fills with this warm, savory smell that makes everyone stop what they're doing. My partner walked in on a random Tuesday evening, saw me pulling one out, and suddenly we had an impromptu dinner party with friends who just happened to text at exactly the right moment. That's the magic of a frittata, honestly, it transforms a quiet evening into something that feels intentional and generous.

Vegetables You Can Swap In Without Thinking Twice

The beauty of a frittata is that it's honestly just a delivery system for whatever vegetables are hanging around. Spinach wilts right in and adds an earthy depth, mushrooms get tender and almost meaty, asparagus stays crisp and sophisticated, and even leftover roasted vegetables work beautifully. The only rule is not to add anything watery without patting it dry first, because excess moisture will make the eggs weepy.

Making It Work For Your Diet

If dairy isn't your thing, swap milk for oat or almond milk and skip the cheese entirely or use vegan cheese, which honestly melts and browns better than you'd expect. The eggs alone are enough fat and richness that you won't miss the dairy nearly as much as you think you will. I've made this for friends with all kinds of dietary preferences, and everyone has had the same moment of surprise when they realized frittata is just inherently adaptable.

Storing, Reheating, and Other Practical Wisdom

Leftover frittata keeps in the fridge for three or four days, which means you can slice a wedge cold straight from the container and eat it standing up at midnight if your life is anything like mine. Reheating it for five minutes in a 300-degree oven brings back the warmth without drying it out further, or you can microwave a slice for 30 seconds if you're in a hurry and have already given up on perfection for the day.

• A green salad on the side makes it feel intentional, while crusty bread turns it into something people actually fight over.
• Pair it with a chilled Sauvignon Blanc if you're feeling fancy, or just drink whatever's open because honestly frittata goes with everything.
• Experiment with cheese types because sharp cheddar hits different than feta, and goat cheese brings an unexpected richness that people always comment on.

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A frittata is the kind of recipe that quietly becomes part of your regular rotation because it works, tastes good, and makes you feel like you have your life together even when you're definitely just throwing things in a pan. Make it this week and you'll find yourself making it again next month, probably with different vegetables but the same easy confidence.

Recipe FAQs

→ What vegetables work best in this frittata?

Broccoli, bell peppers, zucchini, cherry tomatoes, and red onion create a colorful mix. You can also use spinach, mushrooms, asparagus, or any seasonal vegetables you prefer.

→ Can I make this dairy-free?

Yes. Use plant-based milk instead of whole milk and either omit the cheese or use a vegan cheese alternative. The texture and flavor will still be delicious.

→ How do I know when the frittata is done?

The center should be set and slightly golden, not jiggly or runny. Insert a knife near the center—if it comes out clean, it's ready to come out of the oven.

→ Can I prepare this ahead of time?

Yes. You can sauté the vegetables in advance and store them refrigerated. When ready to serve, whisk the eggs, combine everything, and bake. It also tastes great served at room temperature.

→ What size skillet should I use?

A 10-inch oven-safe skillet works perfectly. If you use a larger pan, the frittata will be thinner and cook faster. A smaller pan will make it thicker and require more baking time.

→ How should I store leftovers?

Store cooled slices in an airtight container in the refrigerator for up to 3 days. Reheat gently in the microwave or enjoy cold. It's also delicious for lunch the next day.