Yes! That’s the beauty of crustless quiches or any baked egg dishes, like these make-ahead baked eggs or these ones. Once the leftovers are cool, cover them with plastic wrap or transfer to an airtight container, and refrigerate. To reheat, cut off a piece of the quiche and place it on a microwave-proof plate. Pop it into the microwave for 30 seconds to 1 minute, or until hot. It should heat up quickly. Another option is to prep the ingredients ahead of time – blanch the asparagus and whisk the egg mixture – then bake right before serving.