Now then - if your cottage cheese is 'prawn flavoured' it'll be 0.5 syns / 100g if it's fat-free and 1 syn if its low-fat.
Otherwise, if Spud-u-like use separate CC + prawns:
On a green day, prawns would be syn'd (1 syn / 28g) or 113g as HEb.
Cottage Cheese - low-fat natural 0.5 syns per 100g & fat-free natural = FREE on all 3 plans.
Unless you know how they mix the fillings, it might be worth asking + which CC they use.