My Best Quiche and Crust Recipe Classic Lorraine

Ingredients

• 1 1/4 cups (150g) all-purpose flour, plus more for dusting
• 1/2 teaspoon (3g) salt
• 1/2 cup (113g) unsalted butter, very cold and cubed
• 1/4 cup (60ml) ice water
• 6 ounces (170g) bacon or pancetta, cut into lardons or small dice
• 1 small onion or shallot, finely chopped
• 4 large eggs
• 1 1/2 cups (360ml) heavy cream
• 1/4 teaspoon (1.5g) ground nutmeg
• 1/4 teaspoon (1.5g) salt, plus more to taste
• 1/4 teaspoon (1.5g) black pepper, plus more to taste
• 1 cup (100g) grated Gruyère cheese
• 1 egg yolk
• 1 tablespoon milk or cream