This is one of my favorite banchans (Korean side dishes). Jorim refers to braising, where you let everything cook for a long time so the liquid gets reduced and a thick flavor sauce remains. Many Korean dishes use this method. Here, you slightly pan fry the tofu slices and then add in the spices and water. If the spices aren't evenly dispersed, don't worry! As the liquid boils and cooks, it will disperse on its own.
And make sure your frying pan is big enough to accommodate all the tofu slices. And lay the tofu slices all in one layer to make sure all of them get coated with the spicy, saucy goodness. I like to use a nonstick frying pan to make sure the tofu doesn't stick. Gochugaru, Korean red pepper flakes, is key here! Gochugaru is key in many Korean dishes. If you are cooking a lot of Korean, I highly recommend getting them! I see them more and more in non-Asian grocery stores but in case you can't find them, you can buy some online.
As to gochujang, the ones I saw in non-Asian grocery stores were sweeter so if you do get them, add sugar sparingly, to taste.