Choux cream, probably one of the popular foods in Japan which have Japanese made foreign words.
Choux(plural of chou) means cabbage in French. Choux cream is a confection similar to French "Chou à la crème" or profiterole. The significant difference is that profiterole is like a sandwich, you can see the filling, cream easily. On the other hand, filling choux cream is injected inside the pastry which means you can not see the cream easily.
Choux cream can be found at confectionery and also at supermarkets and convenience stores. By the way, there is a similar pastry which is called eclair. Although choux cream is a round shape, eclair is a hot dog shape and glazed with chocolate or coffee cream.