📖 Instructions

1. First things first, get your oven ready! Preheat your oven to a good, solid 375°F (190°C). This ensures it’s piping hot and ready to go when your frittata is. While the oven is heating, grab your trusty 10-inch oven-safe skillet. If you’re using a cast iron skillet, which I totally recommend for that perfect crust, give it a light coating of olive oil to make sure nothing sticks. If it’s a non-stick oven-safe pan, a little spray of cooking oil should do the trick. Set it aside for a moment.
2. Now for the fun part: veggie prep! Take your zucchini and bell pepper. Wash them thoroughly. For the zucchini, trim off both ends, then slice it into quarter-inch thick rounds. If your zucchini is particularly large, you might want to halve the rounds for bite-sized pieces. Next, for the bell pepper (any color works, but I love red or yellow for sweetness!), remove the stem and seeds, then chop it into small, roughly half-inch pieces. Halve your cherry tomatoes. Give your fresh spinach a good rinse and pat it dry. If using a small onion, peel and finely chop it. Similarly, peel and mince your garlic cloves.
3. Time to get cooking on the stovetop! Place your prepared skillet over medium heat. Add 1 tablespoon of olive oil. Once the oil shimmers, toss in your chopped onion. Sauté the onion for about 3-4 minutes, stirring occasionally, until it becomes soft and translucent. We're building flavor here, so don't rush it! Once the onion is soft, add the minced garlic and cook for another minute, until fragrant. Be careful not to burn the garlic—burnt garlic tastes bitter, and we don't want that!
4. Next, add the heartier vegetables. Stir in the chopped bell pepper and zucchini slices. Cook these for about 5-7 minutes, stirring periodically, until they start to soften slightly but still have a little bite to them. You don't want them mushy, just tender-crisp. Then, add the halved cherry tomatoes and the fresh spinach. Cook for another 2-3 minutes, just until the spinach wilts down completely. Once everything is cooked, remove the skillet from the heat, and give the veggies a gentle stir to mix them all together evenly.
5. While the veggies are doing their thing, let's get the egg mixture ready. In a large mixing bowl, crack all 8 large eggs. Add the milk (whole milk gives a richer frittata, but 2% is fine too!). Season generously with 1/2 teaspoon of salt and 1/4 teaspoon of black pepper. This is also a good time to add any other seasonings you love – maybe a pinch of dried oregano or some red pepper flakes for a little zing. Grab your whisk and whisk the eggs vigorously until the yolks and whites are completely combined and there’s a little foam on top. You want a smooth, pale yellow mixture. Don't stop until there are no streaks of clear egg white left!
6. Now, assemble the magic. Pour the whisked egg mixture evenly over the sautéed vegetables in the skillet. Make sure the vegetables are spread out nicely so they’re distributed throughout the frittata. Take your shredded cheese (cheddar, mozzarella, or a mix are great here!) and sprinkle it generously over the top of the egg mixture. You can be a little heavy-handed with the cheese; it adds a lovely golden crust.
7. Before moving to the oven, let's start the cooking process on the stove. Place the skillet back over medium-low heat for just 2-3 minutes. You’ll see the edges of the frittata start to set and firm up, but the center will still be very liquidy. This stovetop start helps ensure an even cook and prevents a soggy bottom. It’s a small step that makes a big difference!
8. Carefully transfer the skillet directly into your preheated 375°F (190°C) oven. Bake for 20-25 minutes. How do you know it’s done? The frittata should be puffed up, golden brown on top, and most importantly, the center should be set. If you gently jiggle the pan, there shouldn't be any liquid movement in the middle. If it still looks a bit wobbly, give it a few more minutes. Every oven is a little different, so keep an eye on it!
9. Once cooked to perfection, carefully remove the skillet from the oven. Be super careful, that handle will be hot! Let the frittata rest in the skillet for 5-10 minutes before slicing. This resting period is crucial; it allows the frittata to set completely, making it much easier to cut into neat wedges without falling apart. Plus, it prevents it from deflating too much. After resting, use a spatula to loosen the edges, then slice into wedges right in the skillet. Serve it warm and enjoy that beautiful, flavorful summer goodness!
10. For any leftovers, let the frittata cool completely. Then, transfer it to an airtight container and store it in the refrigerator for up to 3 days. It reheats wonderfully in the microwave for a minute or two, or you can even enjoy it cold straight from the fridge. It makes for a fantastic grab-and-go breakfast or a light lunch. Sometimes, I just pick a piece up with my fingers like a slice of pie. No judgement here!