Place cooked chick peas in a blender. Add onion, parsley, garlic, stock, soda, spices, salt & pepper. Process until smooth. Place in a glass bowl & refrigerate until firm, 20 to 30 minutes.
Shape into 12 patties. Dust lightly with flour & fry in hot oil, turning frequently until browned & crisp. Drain on paper towels. Put a pattie in a pita pocket, top with salad & a little harissa if desired.
HARISSA: Place peppers & garlic in a processor & process until coarsely ground. Add remaining ingredients except the olive oil & process until smooth. To store, place in a small jar, top with a thin layer of olive oil & refrigerate till ready to use.
Makes 1 cup.