hot water

Question

I mean if one sees on shabbat morning that his chulent is drying out, is it permitted for a sephardi to add hot water to the pot? If it is, how must it be done? In other words if a pot of food is on the fire, for example a crock pot, and he sees the food is getting dried out. He knows it will sit on the fire for another few hours until lunch. Can he take hot water from a kettle or an urn and pour it into the pot while it is still on the fire to stop it from drying out any more? I hope this is clear. Thank you