Place chicken in a large bowl. Add lemon juice, vinegar, soy sauce, plain flour, mustard paste, ginger garlic, red chili, black pepper and salt.
Mix to coat evenly.
Marinate for 30 minutes to blend flavors.
Preheat oven to 180 degree C.
Place chicken pieces in a greased baking dish or tray.
Bake, in the preheated oven, for 20 minutes or until chicken is done.
Remove from the oven and cut the chicken meat in chunks or strips.
Set aside and keep warm.
Cut the buns in half and toast.
Place lettuce leaves and tomato slices on the bottom half of the each bun.
Put roasted chicken pieces and Mozzarella cheese.
Cover with the top of the bun. Press down. Delicious Chicken Roast Burger is ready to serve. ENJOY!