1 unbaked Pie Crust (recipe follows) or a store-bought 9-inch pie crust
1 1/4 cups all-purpose flour, plus more for rolling
1 teaspoon kosher salt
8 tablespoons (1 stick) unsalted butter, cut into 1/2-inch cubes and chilled
1/4 cup ice cold water
Preheat the oven to 350°F.
Using a vegetable peeler, slice the asparagus lengthwise into long, thin strips, starting just under the tip of each stalk. Leave the tips whole. (Alternatively, cut the asparagus into 1-inch pieces)
In a pot with a steamer insert or in a covered saute pan fitted with an expandable steamer basket, bring 2 inches of water to a boil. Add the asparagus to the steamer insert or basket, cover, and steam until tender, about 30 seconds for strips and 3 minutes for pieces.
Rinse the asparagus under cold water to stop the cooking. Drain well and set aside.
In a large bowl, whisk together the eggs, cream, garlic salt, and pepper. Stir in the fontina, Gruyere, and reserved asparagus.
Pour the mixture into the unbaked pie shell.
Bake until lightly golden and set in the center when the pan is gently pushed, 40 to 45 minutes. If the crust is browning too quickly, cover it with foil to prevent it from burning.
Remove from the oven and let stand for 5 to 10 minutes before serving. Cut into 6 or 8 slices and serve warm or at room temperature.
The quiche is best served the day it is made. Tightly wrap leftovers with plastic wrap and store in the refrigerator for up to 2 days.
In a large bowl, whisk together the flour and salt. Scatter the butter and use a pastry blender or your fingers to cut the butter into the flour until the biggest pieces are the size of small peas. Gradually drizzle the water on top, using a rubber spatula or your hands to stir until the dough comes together. (The dough should not be watery or wet.)
Shape the dough into a flattened ball. Wrap it tightly in plastic wrap and refrigerate for at least 1 hour, or up to overnight.
Lightly dust the counter with flour and roll the dough out to a round 2 1/2 inches larger than a 9-inch pie plate. Transfer the dough to the pie plate and carefully ease it into the edges. Trim the dough to an even 1/2 inch all around and fold it under itself on top of the rim. Refrigerate for 1 hour.