Interesting thread, Moikel. I'm rather late in finding it, but glad that I did. Over the years, I've spent a fair amount of time on Mauritius as well as it's nearby estranged sibling, Reunion Island. The rougailles of Mauritius and the rougails of RI are very similar and are a daily staple and served in a seemingly infinite number of ways - as a component of a meat or seafood dish such as yours, as a side dish or accompaniment, as a stand alone dish, and even as the filling in a roll. The dish is simply a chunky/coarse spicy tomato sauce of Malagasy Creole origins. Beyond a tomato base the common ingredients are onions, garlic, ginger, thyme, parsley, coriander (cilantro), and hot chili peppers. The folks on RI often add cloves to the mix. I've never encountered curry powders in the dish, though I suppose one could add them if desired. Though in the same family of the Louisiana Creole sauce, it's very different dish.
The blend of the cultures and foodstuffs on the island is the result of of it's colonization, and it's keepers and inhabitants along the way. Mauritius has no native population. It was an undiscovered and uninhabited island until the 1500s when the Portuguese explored it. With the exception of hastening the extinction of the dodo bird, they didn't do much and left early on. In the 1600s, the Dutch settled the island, and laid the groundwork for the sugar cane industry. After a period of time, they lost interest in their venture and the French assumed control in the early 1700s. The French established a major naval base there, and greatly expanded the cane industry. For labor, slaves were brought in from nearby Madagascar and East Africa. During the Napoleonic wars, the British took control of the island, and significantly expanded it's military facilities. Other than that, the Brits didn't do much to impact or tamper with the island except to abolish slavery in the mid 1800s. Most of the slaves fled the cane plantations, and many of those remained on the island. This action created a major problem for the plantation owners so they came up with a scheme to import huge numbers of indentured laborers from India with terms that had them working their butts off for 5 years, after which they regained their freedom and a small plot of land. Some Chinese voluntarily followed the Indian flock to the cane fields, but more came, and doing what the Chinese did best in those times, they developed the infrastructure of the supporting retail industry as shopkeepers, etc. Independence from the Brits was attained in the 1960s.
Today, curries and rougailles dominate the food choices on the island. Chinese food is sparsely available in restaurants owned by those of Chinese descent, which serve primarily Cantonese cuisine. Traditional French or British cuisine is essentially non-existent. This isn't surprising since Indo-Mauritians make up 68% of the population and the Creoles come in at 27%. The Franco-Mauritians and Sino-Mauritians split the remaining 5%.
All in all, it's a very interesting part of the world, especially for those seeking new and unique foods. I think that I need to get back there soon.