The primary ingredient in tabouli salad is bulgur wheat, which is soaked and mixed with finely chopped parsley, tomatoes, mint, onions, and sometimes cucumbers. On the other hand, Fattoush salad features a variety of fresh vegetables like lettuce, tomatoes, cucumbers, radishes, and herbs like mint and parsley. The base of tabouli is bulgur and parsley, while fattoush has a lettuce base.