Bake muffins as per recipe and let them cool completely on a wire rack.
Place muffins in a gallon size Ziploc bag, as many as you can fit comfortably.
Seal almost shut, leaving a small opening. Insert straw in it, suck out as much air as possible, remove straw and seal immediately.
Lay muffins flat in a freezer and freeze for up to 3 months. Muffins should be frozen solid after 4 hours.
Notes
Thaw: Defrost muffins in the fridge overnight or on a countertop for 1-2 hours.Reheat: Reheat muffins from frozen or thawed in a microwave in 30 seconds increments. Air fryer is also great for that!