Blue Curacao

From Distillers Wiki

Blue Curaçao is a deep blue liqueur flavoured with the dried peels of bitter oranges grown on the island of Curaçao.

It has an orange flavor, with varying degrees of bitterness, but is used primarily as a coloring agent in cocktails and other mixed drinks. Although blue is the most famous version, curaçao liqueur is also produced clear, or with orange or green coloring.