Mix the flour and a pinch of salt in a bowl, then cut in the cold butter using a pastry cutter or your fingers until the mixture resembles coarse crumbs.
Add ice water one tablespoon at a time, gently mixing until the dough just comes together. Shape into a disc, wrap in plastic, and chill in the fridge for at least 30 minutes to relax the gluten.
Preheat your oven to 190°C (375°F). On a lightly floured surface, roll out the chilled dough to about 0.5 cm thick and fit it into a 23 cm (9-inch) pie or tart pan. Trim the excess dough, prick the bottom with a fork, then line with parchment paper and fill with pie weights or dried beans. Bake blind for 15 minutes until the crust just starts to set.
While the crust bakes, sauté the chopped spinach in a skillet over medium heat with a teaspoon of oil until wilted, about 2 minutes. Let it cool slightly, then squeeze out excess moisture and set aside.
Remove the crust from the oven and take out the parchment and weights. Return the crust to the oven and bake for another 10 minutes until golden and crispy.
In a bowl, whisk together the eggs, heavy cream, grated nutmeg, and season with salt and pepper. Whisk until smooth and just combined, avoiding overmixing for a silky custard.
Stir the sautéed spinach and grated cheese into the custard mixture, folding gently until evenly distributed.
Pour the filling into the pre-baked crust, smoothing the top with a spatula. Place the quiche on a baking sheet and bake for 35-40 minutes, until the custard is set and the top is golden with a slight crackle.
Check for doneness: the top should be golden and puffed, with a firm center that doesn’t jiggle when gently shaken. If the top browns too quickly, tent with foil.
Remove the quiche from the oven and let it rest on a wire rack for at least 10 minutes. This helps the custard set and makes slicing easier.
Slice into wedges and serve warm or at room temperature, enjoying the crispy crust and creamy filling with your favorite brunch sides.
