Changes

If you have a controlled heat source, you can also make a mash tun from any pot large enough to hold the mash. In this case you just raise the heat on the pot, stirring as you go, until you reach your target temperature. Now you turn the heat down to maintain that temperature. The challenge is that it is difficult to maintain a steady temperature for a long time with a pot on a stove. However, commercial brewers who have temperature control systems do successfully use heated mash tuns to mash.