Right. As
badjak says, this has a few names, 'congee', 'zhou' and also 'bubur'. It's very common in this part of the world and has Chinese origins as a way of making a cup of rice go a long way. It's often eaten for breakfast or brunch. In this case today, I made it because my son has a sore throat so trying not to give him anything oily.
Basically cooked rice is immersed in water or stock (I use a thin chicken stock, plus a bit of Knorr chicken powder) then boiled for a long time topping up with water until the grains break down and takes on a sludgy texture. The basic version (water only) is very tasteless so it's usually served with toppings such as bits of meat, tofu, veg etc.. if you're really poor, then just soy sauce!
But since I use stock, the porridge is very tasty and I could easily eat a whole bowl of it by itself, but I add some bits of veg and meat (here it's air-fried sliced fish), and put in a few drops of soy sauce.
