Pastry is cooked and heated in a convection oven. However most things are done differently in Thailand and microwaves are more often than not the convenient alternative and microwaves will turn even the best pastry into soggy mess. In a no option situation place your pie on a moisture absorbant paper towel. Pierce a couple of times to let it breathe and place another sheet of paper over the top.
Heat for three or four minutes in a 600w microwave oven, letting your pie stand for awhile after removing it from the oven