In a medium mixing bowl whisk together flour, sugar and salt.
Add butter and using a pastry cutter cut butter into flour until it resembles coarse meal with some slightly larger clumps of butter throughout.
Drizzle in water 1 Tbsp at a time, tossing and mixing after each addition, and adding just enough water until mixture is just moistened enough (when pressed together with your hand it should hold together).
Dump mixture onto a clean work surface then press together well into a round disk. Flatten to about 6-inch disk and wrap with plastic wrap or transfer to a container.
Chill 1 hour in refrigerator.
Roll chilled dough out onto a floured surface to about a 13-inch round. Roll and wrap dough around a rolling pin then transfer to a 9 to 9 1/2-inch deep dish pie pan.
Unroll dough into pan then shape into pan. Trim uneven edges while leaving about 1-inch overhang, fold overhang underneath. Decorate edges as desired.
Freeze dough for 20 minutes or refrigerate for 1 hour. Meanwhile move oven rack one level below center preheat oven to 350 degrees.
Cover crust with aluminum foil, pressing directly against bottom and side surfaces and leaving foil overhang to drape over edges of crust to prevent over-browning. Fill with dry beans, sugar or pie weights.
Set crust on a baking sheet, then bake in preheated oven 25 minutes.
Remove foil and beans. Pierce bottom and sides all over with a fork and continue to bake until crust appears dried, about 10 minutes longer.
While crust is baking prepare the quiche filling so you can pour into a warm crust.
In a mixing bowl whisk eggs with a fork until blended.
Add heavy cream, ham, cheese, green onions, parsley and season with salt and pepper to taste. Stir mixture until blended.
Pour mixture into pie crust. Bake in preheated 350 degree oven (one level below center of oven) until center of quiche is just barely set, about 45 - 55 minutes. If needed tent crust edges with a pie shield or a foil ring to prevent excessive browning during the last 15 minutes.
Let rest for a few minutes before slicing. Serve warm.
Store-bought Crust Option
For an easy quiche recipe you can use a store-bought, frozen deep-dish pie crust.
If doing so thaw 10 minutes. Pierce bottom and sides all over with a fork.
Bake crust in preheated 400 degree oven for 10 minutes until dry (seal up an cracks with a mixture of 1 Tbsp water 1 Tbsp flour, bake a minute longer).
Reduce custard mixture to 1 cup heavy cream and 4 large eggs. Reduce bake time for filled quiche by about 5 minutes or so.
Use up to 2 cups in place of ham listed.
COOKED MEATS: Bacon, chicken, turkey, breakfast sausage, Italian sausage, chorizo, salami, pastrami, smoked salmon, or crab meat.
VEGETABLES: Mushrooms, grape tomatoes (or sun-dried), bell peppers, broccoli, cauliflower, asparagus, olives, kale, spinach, radicchio, arugula, peas, potatoes, zucchini onion or shallot. Note that the vegetables should be cooked beforehand by sautéing, steaming or roasting.
CHEESES: Cheddar, Swiss, gruyere, Monterrey jack or pepper jack, mozzarella, Romano, parmesan, goat cheese, feta, provolone, gouda, fontina, or ricotta.
HERBS and SEASONINGS: Basil, parsley, chives, tarragon, dill, thyme, marjoram, chervil, oregano, red pepper flakes, paprika, or nutmeg.