Prepare the pastry crust according to the recipe directions (note: the recipe will yield 2 crusts. Feel free to either half the recipe or freeze the second half for a later time).
Preheat the oven to 425 degrees F. Roll the dough into a 12-inch circle, then fit it into a 9-inch pie plate (not deep dish). Trim the crust so it overhangs the plate edge by about 1 inch all the way around, then tuck the edges under at the plate edge and crimp with your fingers or a fork.
Prick the bottom of the crust all over with a fork at 1/2-inch intervals, then line the plate with foil or parchment paper. Fill with dry beans, uncooked rice, or pie weights, ensuring that the beans or weights are all the way up against the edges of the pan. Set on a rimmed baking sheet, then bake for 15 minutes. Remove the lining and weights. If the crust has puffed up in spots, gently press it back down with a fork. Bake, uncovered, for 8-10 additional minutes, until the bottom of the crust is lightly golden. Remove from oven and set aside. Reduce the oven temperature to 375 degrees F.
Meanwhile, place the sundried tomatoes in a small bowl and cover them with boiling water. Let sit for 5 minutes to rehydrate, then drain and pat dry.
In a large bowl whisk together the eggs, egg whites, milk, Greek yogurt, pesto, salt, and pepper. Then, stir in the spinach, Parmesan, and sundried tomatoes.
With the pie plate still on the baking sheet, carefully pour the filling into the prebaked crust.
Bake until the quiche is puffed and the center is set but still a little jiggly, 40 to 50 minutes. If the crust starts to brown too quickly as the quiche bakes, wrap the edges of the pan with foil to protect it. Let quiche cool on a wire rack for 15 minutes. Slice and serve warm or at room temperature.
Notes
MAKE AHEAD: Prepare the recipe as directed then freeze until ready to serve. To bake from frozen remove from the freezer and let stand for about 10 minutes to take some chill off of the pan. Preheat oven to 350 degrees F, tenting as necessary to prevent overbrowning, then bake for 20 to 25 minutes or until heated through.
TOSTORE: Leftover quiche may be stored in the refrigerator for up to 3 days.
TO FREEZE: Pastry dough may be frozen, unbaked, for up to 3 months. Fully baked quiche may be well wrapped and frozen for up to 2 months if wrapped tightly in plastic and a layer of foil.
TO REHEAT: Leftover quiche may be warmed in a 350 degree F oven until heated through. Individual slices of quiche may also be gently microwaved on a microwave-safe plate until steaming.