Vergoise sugar is a French brown sugar. It's very similar to the the Belgian cassonade. Since I can't find cassonade in London, I use the vergoise instead.
I buy the Beghin Say saveur Vergeoise Blonde goût Vanille.
Where to buy it:
* I haven't found it yet in any shop in the UK
* I order it online @ https://www.europafoodxb.com/