1. Saute onion and green pepper in oil. Add salt & pepper.
2. Add some salt, ginger, and cracked pepper to beef slices and brown on both sides in oil.
3. Mix together yogurt, dressing, and lemon juice. Set aside.
4. Warm pitas in microwave or oven. Cut open pitas and stuff with some romaine lettuce. Put sliced tomato on top of lettuce and green pepper/onion mix on top of tomato slices. Put slice of beef on top of pepper mix. Add generous amount of yogurt mixture.