If liquors are the backbone of the cocktail world, then liqueurs could be thought of as their sweeter, more playful sibling. Unlike standard liquor,  these spirits are high in sugar and often (but not always!) lower in alcohol content as a result. Better yet, the options for flavorings and infusions are practically unlimited– you’ll find liqueurs made with everything from fruit to herbs, nuts, spices, flowers, and even flakes of gold.   While today’s liqueurs are mostly used to give complexity…