This black chocolate, in the shape of a champagne cork, was created in 1951.
Measuring less than an inch, these small chocolates are meant to melt in your mouth, or crunch between your teeth if you bite into them, revealing a liquid centre filled with Marc de Champagne (a brandy).
Sometimes also found enrobed in a certain kind of sweet, Marc de Champagne is made by distilling the grape skins, seeds, and stalks which are left from the pressing process in the first stages of Champagne production, which is why it has such a high alcohol level. Indeed, it can be 40% alcohol but is generally only 20% (but still!).
To really make the link obvious, the chocolate is then wrapped in a foil which is identical in colour and texture to those found on a genuine champagne cork.