I never measure anything, but I use:

either beef or beef mixed with pork, onions, sometimes green onions, ginger, garlic, all sauteed in sesame oil.

Then add: water, a little sake and soy sauce, oyster sauce, sugar, doubanjiang, tianmianjiang, tofu obviously, maybe some chili oil. Next time I'm going to try using Korean chili paste. You can add starch, too.