The microwave works fine for me. I place it in a bowl and add either finishing pepper sauce or BBQ sauce to it and hit high for 30-40 seconds then stir and serve... Keep in mind at one time, the meat was up to 205 degrees minimum if you smoked it for pulling. the microwave works fine.
If I had a food sealer, I'd probably pack up individuals, add a little sauce and freeze. Then all ya have to do is heat in boiling water and you can keep em frozen until ready to use.
I assume you are referring to already pulled pork placed in a fridge since you stated "pulled pork". If however you meant an entire shoulder or picnic, in foil, oven at 325 until center reads 140. Allow to cool then pull, shred.