Zucchini and Feta Frittata

This is a frittata of eight eggs, a pound of zucchini, red onion, feta, and dill, started on the stove in a 10-inch oven-safe skillet and finished in the oven.

The zucchini and onion cook in the skillet for five to eight minutes until the pan is dry before the eggs go in, so the water the zucchini gives off cooks away instead of ending up under the slices. Half the feta is whisked into the eggs and half goes on top, so it seasons every bite and still sits in soft pieces on the surface. It bakes at 375°F until the center has just set and comes out before it puffs.

It makes six slices and is as good cold from the fridge as it is warm.

Why You’ll Love It

• Five ingredients plus oil, salt, and pepper.
• One 10-inch skillet, about 35 minutes.
• Keeps 4 days in the fridge.
• Eats cold, so it packs for lunch without a microwave.
• Vegetarian and gluten-free.

Ingredients

8 large eggs

3/4 teaspoon kosher salt

1/2 teaspoon black pepper

2 tablespoons olive oil

1 small red onion, thinly sliced

1 lb zucchini, about 2 medium, sliced into thin half-moons

4 oz block feta, crumbled, about 3/4 cup

3 tablespoons chopped fresh dill

Steps

1. Preheat the oven to 375°F (190°C).

2. Whisk the eggs in a large bowl with the salt and pepper until no streaks of white remain and the surface is a little frothy. Stir in half the feta and half the dill. Set aside.

3. Pat the zucchini slices dry with paper towels. This takes 30 seconds and removes the water sitting on the cut surfaces.

4. Heat the olive oil in a 10-inch oven-safe skillet over medium heat. Cast iron or an oven-safe nonstick pan both work. Add the onion and cook for 3 to 4 minutes until soft.

5. Add the zucchini and a pinch of salt. Cook for 5 to 8 minutes, stirring occasionally, until the zucchini is tender and lightly golden and there is no liquid pooled in the pan. If you see liquid, keep cooking. This is the step that decides whether the frittata is watery.

6. Spread the vegetables evenly across the pan, turn the heat to medium-low, and wait 30 seconds so the pan isn’t screaming hot. Pour the eggs over the top and give one gentle stir so the vegetables are distributed. Then leave it.

7. Cook on the stove for 3 to 5 minutes until the edges are set and pulling away from the pan slightly. The center will still be liquid.

8. Scatter the remaining feta over the top and move the skillet to the oven. Bake for 10 to 15 minutes until the center is just set. Press the middle with a fingertip. It should be firm with no jiggle, and the top should be barely golden, not brown. If it’s puffed up like a soufflé, it’s overdone.

9. Let it rest in the pan for 5 minutes, then run a spatula around the edge and slide it onto a board. Top with the remaining dill and cut into 6 wedges.

Helpful Tips and Substitutions

Pull it from the oven when the center has just set. It keeps cooking from the residual heat of the skillet for several minutes. A frittata that’s fully firm in the oven is rubbery on the plate. This is the mistake nearly everyone makes.

Small and medium zucchini have fewer seeds and less water than large ones. If you’re using one big zucchini, scoop out the seedy center with a spoon before slicing.

Salt the eggs lightly. Feta is salty and half of it is going into the egg mixture.

Half the feta goes in the eggs and half on top for a reason. The feta inside seasons every bite, and the feta on top stays in soft pieces instead of dissolving.

Cast iron browns the bottom more and holds heat longer, so start checking at 10 minutes. In a nonstick pan it can take the full 15.

A quarter cup of cream or whole milk whisked into the eggs makes it more tender. It’s optional, and it’s not needed if you pull it from the oven on time.

Swap goat cheese or ricotta salata for the feta. Basil, mint, or parsley for the dill. Leeks for the red onion. A cup of halved cherry tomatoes, well drained, can go in with the zucchini for the last 2 minutes.

Serving Ideas

Warm for dinner with a green salad and bread.

Cold or room temperature for lunch, on its own or in a sandwich with a spread of Greek yogurt.

Cut into small squares instead of wedges for a picnic or a lunchbox.

A spoonful of tzatziki or plain Greek yogurt on the side, and a squeeze of lemon.

Make-Ahead and Storage

Let it cool completely before storing or it sweats in the container.

Keeps in an airtight container in the fridge for 4 days. Slice it before storing so you can grab one piece at a time.

Eat it cold or at room temperature. It’s meant for this. Take a slice out of the fridge 15 minutes before eating and it’s at its best.

To reheat, cover with foil in a 300°F oven for 10 minutes, or microwave a slice for 30 to 45 seconds. Longer than that and the eggs turn rubbery.

Don’t freeze it. Frittata goes spongy and wet on thawing, and the zucchini makes it worse.

The zucchini and onion can be cooked a day ahead and kept in the fridge. Warm them briefly in the skillet before adding the eggs, since cold vegetables set the eggs unevenly.