In general, reheating stuff is hard.
The microwave, while ubiquitous and convenient, is overall pretty much an agent of disaster. Let us first recall what the microwave does. It fires radio waves that are absorbed by water, fat and sugar, and just like a baseball being thrown to an stationary ice-skater, this is turned into motion which at the molecular level is the same as heat.
But there are consequences attached to this. You are effectively only heating the water, fat and sugar portion and depending on statistical mechanics to transmit that energy to the other molecules. It works well enough for many things but not for all. For example, the surface tends to get crusty, or the fat and sugars start to caramelize around the edges, and seafood gets both nasty and tough.
Well, when that happens, it's back to being ol' school. Put up a double boiler. Underneath a bubbling pot of water, and on top a heat-resistant glass bowl with the food. Takes longer to heat but you are guaranteed great results.