Cut cold roast beef into thin strips or chunks, as desired. Prep and chop veggies, assorted peppers and onions and set aside till needed.
Add oil to large skillet, heat over medium high heat. Then add in the peppers and onions, saute until vegetables are translucent about 6-8 minutes.
Now stir in the roast beef strips & extra vegetables, and any additional gravy you had left from the Roast Beef dinner. Saute over medium high heat until beef is heated through.
Serve over cooked rice or pasta. I used Low Sodium Soy Sauce instead of adding additional salt.