Baked Chinese egg tarts can be reheated in the oven or toaster oven at 350 degrees F (176 degrees C) for about 5 to 7 minutes or just until toasty warm. Do not reheat pastries in the microwave or you will end up with a soggy puff pastry crust.  In addition, you can reheat your egg tart in the air fryer. Set the air fryer to 350 degrees F (180 degrees C) and heat for 3 to 4 minutes or until toasty warm in the center.