In a large bowl, mix the whipped topping, sour cream and pudding mix until blended; fold in pineapple. Cut a small hole in the corner of a pastry or plastic bag; fill with pudding mixture.
On a flat serving plate, arrange four crackers in a rectangle. Pipe about 1 cup pudding mixture over crackers; top with about 1/4 cup banana slices. Repeat layers five times. Cover and refrigerate overnight.
Before serving, top with chocolate syrup, strawberries and banana slices. Yield: 10 servings.