It's not exotic - if you are cooking in the oven then just put some water in a roasting pan and stand the dish containing your pudding in that, if cooking on the stove then you'll need a saucepan big enough to take your pudding bowl and some water.

Water can never get hotter than 100 degrees, so if your pudding is stood in something full of water then it's much less likely to get burnt around the edges.