Preheat and prep: Heat your oven to 375°F (190°C). If using a store-bought crust, place it in a 9-inch pie dish and crimp the edges. Prick the base with a fork.

Blind bake the crust: Line the crust with parchment and fill with pie weights or dried beans. Bake 12–15 minutes, remove the weights and parchment, and bake 5 more minutes until lightly golden. Set aside to cool slightly.

Cook the aromatics: In a skillet over medium heat, warm the oil or butter. Sauté the onion with a pinch of salt until soft and translucent, 4–6 minutes. Add the garlic and cook 30 seconds, just until fragrant.

Wilt the spinach: Add fresh spinach by the handful, stirring until wilted. If using frozen spinach, add it now and cook off excess moisture. Transfer the mixture to a colander and press out as much liquid as possible. Excess moisture leads to a soggy quiche.

Mix the custard: In a bowl, whisk the eggs, milk, and cream until smooth. Season with 1/2 teaspoon salt, several grinds of pepper, and a pinch of nutmeg if using. Taste the custard and adjust seasoning, remembering feta is salty.

Assemble the filling: Scatter the spinach-onion mixture evenly over the crust. Sprinkle the crumbled feta and shredded cheese over the top.

Pour and settle: Slowly pour the custard over the filling, tilting the dish gently so it settles evenly. Don’t overflow the crust; you may have a tablespoon or two of custard left, and that’s fine.

Bake: Reduce oven heat to 350°F (175°C). Bake 30–40 minutes, until the center is just set and wobbles slightly when you nudge the pan. If the crust browns too quickly, tent the edges with foil.

Cool before slicing: Let the quiche rest 15–20 minutes. This helps it firm up and slice cleanly.

Serve: Enjoy warm or at room temperature. A simple side salad with lemon vinaigrette pairs beautifully.