The Waterloo Sunset is a delightful twist on a few cocktails. First, you have the interesting base of gin and elderflower liqueur (St. Germain being the liqueur of choice) in a Champagne cocktail that mimics an Elderflower Cocktail.
Then, there is the element of the "sunrise" that is most commonly found in a Tequila Sunrise. In this case, however, the "rise" is attributed to raspberry liqueur instead of grenadine, with Chambord being the most convenient and highest quality choice. It is a stunning cocktail for celebrating any occasion.