Flatten the beef fillets with the flat end of a knife. Marinate them for half an hour with salt, ginger garlic paste and vinegar.
Add chili sauce and sprinkle black pepper on the beef fillets.
\Grease a grill pan and heat on a medium flame. Grill the fillets from both the sides until tender.
Slice the buns into two halves. Spread Blue Band margarine onto one half and place the fillet on top. Place a lettuce leaf and cover the bun with the other half.
Serve this delicious barbeque sandwich with tomato and chili garlic sauce.