Ham and mushrooms are a perfect match, and welcome partners in almost any season. But I prepare this most often in the winter months, serving it as a lunchtime treat.
8 SERVINGS
EQUIPMENT: A large nonstick skillet with a lid; a 10-inch (25 cm) round baking dish.
Extra-virgin olive oil, for oiling the dish
6 large eggs, free-range and organic
1 teaspoon fine sea salt
1 tablespoon fresh oregano leaves, or 1 teaspoon dried
4 tablespoons (60 g) unsalted butter
3 medium onions, peeled, halved lengthwise, and cut into thin half-moons
8 ounces (250 g) fresh mushrooms, trimmed and thinly sliced lengthwise
1 tablespoon coarsely grated organic lemon or orange zest
1/2 cup (2-1/2 ounces/75 g) cooked ham, cut into 2 x 1/4-inch (5 cm x 5 mm) matchsticks
1/4 cup (25 g) freshly grated Parmigiano-Reggiano cheese
3 tablespoons finely minced fresh chives, for garnish
1. Center a rack in the oven. Preheat the oven to 400°F (200°C). Lightly brush the baking dish with oil.
2. Crack the eggs into a bowl. Add 1/2 teaspoon of the salt and the oregano. Whisk to blend.
3. In the skillet, combine half the butter, onions, and 1/4 teaspoon salt and sweat—cook, covered, over low heat—until soft and translucent, about 5 minutes. Do not let the onions brown. Transfer the onions to the baking dish.
4. In the same skillet, combine the remaining butter, mushrooms, and the remaining 1/4 teaspoon salt and sweat—cook, covered, over low heat—until soft, about 5 minutes. Arrange the mushrooms on top of the onions and sprinkle with the citrus zest. Dot with the ham matchsticks. Pour the eggs over all. Sprinkle the Parmesan on top. (The dish can be prepared up to 1 hour before baking. Store at room temperature.)
5. Bake until the eggs are firm and the top is a deep golden brown, 20 to 30 minutes. Garnish with the chives. Cut into 8 wedges and serve warm.