NOTE: If you don't have a steamer, here's an alternative
Invert an aluminum pie pan into the bottom of a large stew pot and place some husks on top of the pie pan.
Arrange the tamales in the pot by placing them one by one open side up on top of the pie pan, starting in the middle and working out, building a pyramid, Fill the pot about 1/2 full with tamales.
Pour enough water seasoned with a little salt and chili powder into the bottom of the pot (not on the tamales) to not quite touch the bottom of the tamales.
Steam, covered, about 2 hours on very low heat.