Recipe adapted from Egg White Breakfast Cups from Tasty.
Make sure to run a pairing knife around egg cups and remove them from the pan using a spoon. Otherwise they may stick to the pan once cool.
STORAGE: Keep breakfast egg cups in an airtight container for up to 5-7 days in the refrigerator. Microwave 30 seconds to reheat. To freeze, let cool first and then individually wrap each with plastic wrap and foil. To reheat, microwave them for 30-60 seconds or until hot.