There are several locations of Rococo, but their flagship store is in Belgravia. The woman who assisted us was unbelievably friendly and talked knowledgeably and confidently about the chocolates. I loved that she had opinions and actively made suggestions based on our declared preferences.
They have a number of plain dark chocolates, each from different sources, and as a result, each with a different taste. One of these is their house truffle, which is dusted in 100% cocoa. The plain dark chocolates (4 options) range from 63% to 74% dark, are square shaped, and very thin. We asked her to pick her favorite of the four (which apparently was not the house truffle) and we purchased it. It was good, not great, and nothing to seek out again.
We did not try their hot chocolate, but I do believe it is worth going back to to try. It is supposed to be one of the best. In one section of the shop, they also have coffee and cakes. Their chocolate flourless cake looks to die for. It is fudgey and dense and I’d imagine it’s quite rich. I would recommend trying that as it looks delicious enough for me to be confident in without having tried it.