Preheat the Oven: Preheat your oven to 375°F (190°C). If using a pre-made pie crust, place it on a baking sheet to avoid any spillage during baking.
Prepare the Spinach: If using fresh spinach, sauté it in a pan until wilted, then allow it to cool. If using frozen spinach, thaw it completely and squeeze out any excess water.
Whisk the Eggs and Milk: In a mixing bowl, whisk together the eggs and milk until smooth. Season with salt and pepper to taste.
Add the Spinach: Stir the prepared spinach into the egg mixture. Mix thoroughly to ensure the spinach is evenly distributed throughout.
Pour into the Pie Crust: Carefully pour the spinach and egg mixture into the pie crust. Spread it out evenly.
Bake the Quiche: Place the pie in the preheated oven and bake for 30–35 minutes or until the quiche is set in the center and the top is golden brown.
Cool and Serve: Let the quiche cool for about 10 minutes before slicing. Serve warm for the best flavor or at room temperature.