Boil the potatoes till soft. Peel, mash and keep aside to cool.
Poach the Tilapia filets in boiling water (or in a microwave) till fully cooked, white in colour and easy to flake. Drain the water completely and flake the fish with a fork. Keep aside to cool slightly
Once cooled, mix the Tilapia with potatoes, cilantro, onions, green chilies and all the dry spices. Mixx well. Add the eggs and give it another good mix. Finally stir in the breadcrumbs, and combine well (use your hands!). The mixture should be dry enough to be rolled with the hands. If it's too wet add some more breadcrumbs.
Adjust seasoning, and roll the mixture into 1.5 inch discs (makes around 100 pieces), and keep aside.
Mix all the ingredients for dip and refrigerate for 15-20 mins, while you fry the fishcakes
Heat oil in a non-stick pan. Fry the fishcakes in batches till golden brown on each side. These can be made up to 2 hrs ahead, and kept warm in a 180F oven. Uncooked, they also freeze well for up to 2 weeks.
Serve warm with a dollop of the Sriracha Mayo...and watch them disappear before you can say hello!