Place all of the ingredients for the marinade into a bowl and mix them.
Slice the beef into strips, cutting against the grain.
Marinate the beef strips for 3-4 hours.
While the beef is marinating, slice the bell peppers and celery.
When the beef is done marinating, place the beef strips on a large plate or cutting board, discard the marinade, and pat the beef dry with paper towels.
Please 2 tablespoons of oil into a large skillet and heat on medium-high.
When the oil is hot, add the beef strips and cook on both sides. This should take about 2 minutes on each side.
Remove the beef to a plate or bowl and set aside.
Add a bit more oil to the skillet and add the peppers and celery.
Cook for 5 minutes.
While the vegetables are cooking, prepare the sauce by mixing all of the sauce ingredients in a small bowl.
Add the sauce to the skillet and add the beef strips back to the pan.
Cook for another 3-5 minutes.
Serve with rice.