I don't have much experience with the pressure cooker but what I have done with i has been amazing!
This was a taste bud worthy recipe with really tender pieces of flank steak. It came together quickly and I served it with some brown rice and broccoli.
A definite must make if you have a pressure cooker!
Click here for recipe: http://www.pressurecookingtoday.com/pressure-cooker-mongolian-beef/
Here is the slow cooker method if you don't have a pressure cooker!
Click here for recipe: http://therecipecritic.com/2015/08/slow-cooker-mongolian-beef/