A ganache is a French term which refers to the concoction of heavy cream and chocolate. It is usually produced from cream of heavy consistency which is boiled and then dispensing it on top of chopped up chocolate. This concoction is mixed until it finally is perfectly smooth. The ratio and proportion of the ganache will vary depending on the kind of chocolate the chocolatier wants. For truffles, the usual ratio is two parts of chocolates is to one part of cream.
There are basically four kinds of chocolate truffles that have been circulating the chocolate world. These three are the Swiss truffle, European truffle, American Truffle, and the Belgian truffle.
To produce the Swiss truffle you need to combine chocolate and a boiling concoction of butter and dairy cream. This mixture is then poured into casts for setting. Then cocoa powder is sprinkled unto the chocolate casts. Swiss truffles have a short shelf-life so they must be eaten up within days of production.