Place the ostrich fillets into a bowl. Add the chilli flakes, the all spice, the ground cinnamon, the orange peel of half an orange and the ginger. Add some salt and enough oil to coat. Allow to marinate for 10 minutes.
Place the marinated fillets onto a hot grill for about 3 minutes on each side. Then allow to rest for 3 minutes.
To make the sauce heat the ginger, orange juice and orange peel, then add the pomegranate molasses and maple syrup. Reduce until syrupy. Add the orange segments and butter and allow to cook for a few minutes.
Place a little sauce on the bottom of your serving dish, top with fresh watercress. Slice the fillet and place on top of the watercress. Spoon over additional sauce with orange segments and serve.