A disclaimer: I am not Senegalese, and I have never (sadly) been to Senegal. Furthermore, I've only eaten Senegalese food half a dozen times. At each of these Senegalese restaurants, we were served a sort-of side dish/sauce/relish made of mustardy onions. It was such a perfect complement to grilled chicken, roasted lamb, etc. We loved it! I have reviewed dozens of Senegalese & West African recipes to re-create the flavor, and I have culled ideas from many of them. In restaurants, this sauce has always been semi-spicy, but it never been as spicy as some of the recipes suggested (ie, two+ scotch bonnets). This recipe is my to-date best attempt (as of 2/9/18). This is a non-spicy option - as I generally cook for a range of lovable but wimpy people.