Heat oven to 425° F.
In a large bowl, whisk together the eggs, milk, cream, salt, and pepper.
Prick the bottom of the piecrust several times with a fork. Sprinkle with the Gruyère. Distribute the olives, broccoli or asparagus, and ham into 4 quadrants according to the preferences of each family member. (Or simply place all the ingredients together on the crust.) Pour the egg mixture into the piecrust.
Bake for 15 minutes. Reduce temperature to 350° F and bake for 30 minutes more. Transfer to a rack to cool for 15 minutes. Cut into 8 wedges and serve.
Instead of store-bought piecrust, try this flaky and delicious Pastry Dough.