Skinless and boneless mackerel fillets in a katsu curry sauce

mackerel 53.8% , corn starch 23.1% , tomato purée 11.5% , whole milk powder 5.8% , salt 0.5% , turmeric 0.5% , onion 0.5% , black pepper 0.5% , star anise 0.5% , soya bean 0.5% , clove 0.5% , Acidity regulator 0.5% , wheat flour 1.8%