These perky little stuffed peppers store well in the refrigerator for a few days in a sealed container. To reheat, simply place on a baking sheet or casserole dish. Pop back in the oven at 375 degrees for about 8 minutes. Additionally, you could also microwave them in a glass dish for a minute or two. This reheating method will not be as firm as heating them in the oven or air-fryer.