Classic French Quiche Lorraine

1.Preheat the oven to 190°C (375°F). Prepare the bacon by dicing it and cooking it in a skillet over medium heat until crisp. Remove the bacon with a slotted spoon and drain it on paper towels. Reserve 1 tablespoon of the bacon fat.

2.Blind Bake the Crust: Line the chilled pie crust with parchment paper and fill it with pie weights or dried beans. Bake for 15 minutes. Carefully remove the weights and paper, prick the bottom of the crust lightly with a fork, and return it to the oven for 5 more minutes until lightly golden. Reduce the oven temperature to 175°C (350°F).

3.If using onion, sauté the chopped onion in the reserved tablespoon of bacon fat until softened and translucent, about 5 minutes. Set aside.

4.Assemble the Quiche: Sprinkle the shredded Gruyère cheese evenly over the bottom of the par-baked crust. Distribute the crisp bacon and the sautéed onion (if using) over the cheese.

5.Prepare the Custard: In a medium bowl, whisk together the 3 large eggs and 1 egg yolk until just combined. Whisk in the heavy cream, whole milk, salt, pepper, and nutmeg until smooth. Do not over-whisk, as this can create too many air bubbles.

6.Pour the custard mixture gently over the filling in the pie crust. Ensure the filling is evenly distributed.

7.Bake the Quiche: Carefully transfer the quiche to the preheated 175°C (350°F) oven. Bake for 40 to 50 minutes, or until the custard is set and the top is golden brown. A knife inserted near the center should come out clean (or mostly clean with a slight jiggle in the very center).

8.Cool and Serve: Remove the quiche from the oven and let it cool on a wire rack for at least 15 to 20 minutes before slicing. This allows the custard to fully set. Serve warm or at room temperature.