1-Preparation Phase: First, preheat your oven to 375°F (190°C) and lightly spray a 9-inch pie dish with cooking spray. This ensures your quiche releases easily after baking. While the oven heats, prepare your vegetables. Finely chop the onion, mince the garlic cloves, and roughly chop the fresh spinach.

2-Sautéing the Vegetables: In a skillet over medium heat, warm the olive oil. Add the chopped onion and minced garlic, sautéing them until soft and fragrant, about 3-4 minutes. This step mellows the sharpness of the onions and garlic, creating a sweeter, more subtle flavor base. Next, add the chopped spinach to the skillet. Cook until wilted, which should take just 2-3 minutes. The spinach will reduce significantly in volume as it releases moisture. If you’re using frozen spinach instead of fresh, make sure to thaw it completely and squeeze out all excess moisture before adding it to the pan. This step is crucial because excess water can make your quiche soggy.

3-Creating the Custard Mixture: While the vegetables are cooling slightly, it’s time to prepare the custard. In a large mixing bowl, whisk together the 4 large eggs and ½ cup milk until well combined. For the fluffiest texture, whisk vigorously to incorporate some air into the mixture. Once the eggs and milk are blended, add the shredded Gruyere, crumbled feta, grated Parmesan, pinch of nutmeg, salt, and pepper. Stir until everything is evenly distributed. The combination of these cheeses will create a rich, creamy texture and incredible flavor.

4-Assembling and Baking: Spread the cooked spinach mixture evenly across the bottom of your prepared pie dish. Pour the egg and cheese mixture over the spinach, then gently stir to combine the ingredients in the dish. This ensures that the cheese and spinach are well distributed throughout the quiche rather than layering. Place the dish in the preheated oven and bake for 30-35 minutes. You’ll know it’s done when the top is golden brown and the center is set. To test for doneness, insert a knife into the center of the quiche, it should come out clean. If there’s any liquid on the knife, give it a few more minutes.

5-The Resting Period: This step might be tempting to skip, but don’t! Allow the quiche to rest for a few minutes before slicing. This resting period helps the custard set completely and improves both texture and flavor. It also makes slicing much easier and cleaner.