Marinate the cut beef in some sesame oil for 30 minutes.
In a small pot, mix the sauce: soy sauce, brown sugar, Gochujang sauce, ginger powder, vinegar, sesame oil, onion powder, black pepper, fish sauce and ½ cup water. Stir and bring to boil and remove from heat.
With oil in the pressure cooker pot, brown the beef by frying for a few minutes. Remove and set aside drained.
With oil in the pressure cooker pot, fry garlic and onions for 2 minutes.
Add the meat back into the pot and mix.
Put the cut vegetables into the pot on top of the meat: carrots, potatoes, bell peppers.
Pour the sauce into the pot. Add ½ cup of water.
Pressure-cook for 25 minutes.
Release the pressure and open the pot.