Soondubu recipe - looking for the ultimate recipe (vegetarian)?

can anyone give me their ULTIMATE soondubu recipe? I don't eat fish or any other type of meat. I have tried all types of ingredients across the past few years - from denjang paste to the korean chili powder to vegetarian broth to all of those combined all with mushrooms (the way maangchi on youtube makes it). I still cannot get the wonderful flavor I find in restaurants. YES, I am sure the restaurants put fish in their broth, but at home we don't cook meat. Who has a recipe worthy of sharing!?! :)