There are a few things that make Lindt chocolate so smooth. First, the cocoa butter and milk fat content is higher than other types of chocolate. This gives the chocolate a creamier texture. Second, Lindt chocolate is conched for a longer time than most chocolates. Conching is a process of grinding and mixing the chocolate to create a smoother texture. Finally, Lindt chocolate contains less sugar than other chocolates, which also contributes to its smoothness.