Preheat your oven to 425°F. Place the thawed pie crust into a 9-inch pie pan, letting it settle naturally into the corners without stretching. Prick the bottom and sides all over with a fork to prevent puffing during baking. Line the crust with parchment paper or foil and fill with pie weights or dried beans to keep it flat. Blind bake for 10 minutes until the crust is set but not golden. Remove the weights and parchment carefully, then let the crust cool while you prepare the remaining components. This pre-baking step prevents a soggy bottom and ensures a crisp, professional texture.

Lower your oven temperature to 350°F. While the crust cools, melt the butter in a skillet over medium-high heat. Add the asparagus pieces and cook for 6-8 minutes, stirring occasionally, until tender but still slightly firm—you want them to have a bit of bite since they'll cook again in the quiche. Season lightly with a pinch of salt and pepper. I like to finish the asparagus with just a touch of salt at this stage because it helps draw out their natural sweetness and makes them taste more vibrant than underseasoned asparagus.

While the asparagus cooks, crack the room-temperature eggs into a mixing bowl and whisk them together thoroughly. Pour in the half and half (or heavy cream if you prefer a richer quiche), then add the remaining salt and a generous grind of black pepper. Whisk until the mixture is smooth and well combined—the eggs and cream should be fully incorporated with no visible streaks of egg white. Set this custard mixture aside until you're ready to assemble the quiche.

Spread the shredded Gruyère evenly across the bottom of the pre-baked crust, then scatter the diced ham over the cheese. Distribute the sautéed asparagus from Step 2 in an even layer across the ham. Gently pour the custard mixture from Step 3 over all the fillings, allowing it to settle and fill in the gaps—pour slowly to avoid overfilling. Place the quiche on a baking sheet (this catches any drips and makes handling easier) and transfer to the 350°F oven. Bake for 40-50 minutes until the custard is set around the edges but still has a slight jiggle in the very center—it should register about 160°F on an instant-read thermometer. I find that slightly underbaking ensures the quiche stays moist and creamy rather than rubbery.

Remove the quiche from the oven and let it rest at room temperature for 10 minutes—this allows the residual heat to finish setting the center gently while the structure stabilizes, making it easier to slice cleanly. The quiche will continue to cook slightly during this resting period. Slice into wedges and garnish with fresh chopped parsley just before serving. The quiche can be served warm or at room temperature, making it ideal for both brunch gatherings and make-ahead meals.