A cocoa-based mixture is described for extracting espresso beverages comprising grains of cocoa mass having sizes included between 500 μm and 4000 μm, these grains being then covered with a maltodextrins film so that the coverage of maltodextrins represents a percentage included between 5% and 20% in weight of the mixture of covered grains of cocoa mass. A process for preparing such mixture and a capsule for preparing a beverage from such mixture are also described.