Storing quiche is as simple as wrapping it up and tucking it into the refrigerator or freezer. Firm quiche stores well as individual slices, but if your quiche is runny, keep it in its original baking pan when you store it so it retains its shape.
Refrigerate
Leave the cooked quiche in its baking pan and wrap tightly in plastic wrap or aluminum foil, or slide the pan into a large, resealable plastic bag. If the quiche is sliced, place individual slices into small resealable plastic bags. Use within 3 or 4 days. Serve at room temperature, reheat in the microwave or heat for about 20 minutes in a 350-degree Fahrenheit oven.
Freeze
Cool the quiche to room temperature before freezing. Wrap as you would for refrigeration in airtight freezer wrap, aluminum foil or individual freezer bags. Label the packages with the contents and the date frozen -- quiche will retain its flavor for 1 to 2 months in the freezer, but longer storage will cause the eggs to become rubbery. Frozen quiche can be reheated in a 350 F oven for about half an hour, or until the internal temperature is 160 F, without thawing.