I think of cumin and coriander as ying and yang, two different but intertwined spices. The one brings out the best in the other. This is what makes the North African chermoula so very irresistible. Here, the addition of fresh herbs ensures that this spicy, zesty sauce raises the humble potato to new heights. More to the point, I thought of this potato dish as a North African cousin to the Spanish patatas bravas.