If frozen, these are best reheated in an oven at 350 degrees Fahrenheit for 10-15 minutes or until warmed through. I use my small airfryer convection oven, and place them directly on a rack and set the timer to 10 minutes. Don't wait for the oven to preheat as that thaws out the muffins. You can also cut it in half to warm it quickly. If you so desire to reheat in microwave, just warm them up for 1 minute from frozen or 30 seconds if refrigerated.