I got this out of Martha Stewart's Everyday Food. Of course I did have to save the other half of the gruyere block to make this.
1 tablespoon butter
1 leek (white and light green parts only), halved and thinly sliced, then well washed
coarse salt and ground pepper
1 bunch (1 pound) asparagus, tough ends removed, thinly sliced on the diagonal
4 large eggs
1 1/4 cups half-and-half
One 9 in. pie crust, well chilled
1 cup shredded Gruyere cheese (4 ounces)
Preheat oven to 350 degrees F, with rack in lowest position. In a large skillet, melt butter over medium. Add leek and asparagus; season with salt and pepper. Cook, stirring occasionally, until asparagus is crisp-tender, 6 to 8 minutes; let cool.
In a large bowl, whisk together eggs, half-and-half, 1/2 teaspoon salt, teaspoon pepper, and a pinch of nutmeg. Place pie crust on a rimmed baking sheet. Sprinkle with cheese; top with asparagus mixture. Pour egg mixture on top.
Bake until center of quiche is just set, 50 to 60 minutes, rotating sheet halfway through. Let stand 15 minutes before serving. (To store, let cool, then refrigerate, up to 1 day. Reheat at 350 degrees until warm in center, about 30 minutes.)