<P> The Frosty is the signature frozen dairy dessert of Wendy's fast - food restaurants, introduced in 1969 when the first restaurant opened . The Frosty's original light chocolate flavor, actually a combination of chocolate and vanilla, was initially the only flavor offered . Wendy's founder Dave Thomas thought that a pure chocolate flavor would overwhelm the taste of the restaurant's hamburgers . In August 2006, a vanilla flavor was introduced after repeated consumer requests . </P>

When did wendy's release the vanilla frosty