If you don't have a pressure cooker, steam on the stovetop in a tightly-lidded steamer over medium heat for about 80-90 minutes depending on how deep your bowl is. Be sure to add enough water for the long process! It is difficult to overcook, and you can simply steam longer in 5-10 minute increments if it's not tender enough to your liking. You can start checking for fork-tenderness after 70 minutes.