I suggest reheating sweet potato crust quiche from a thawed out state. Once they are thawed out, place them in a single layer on a sprayed or oiled baking sheet. Bake at 350° F for 10-15 minutes, just long enough to heat them all the way through. I don't recommend using a microwave to heat up sweet potato crust quiche bites as they the crust may turn out a little chewy.