Blue Lagoon

Bitter orange peel and sugar, essentially. Curaçao is an orange liqueur made from dried laraha peel, and the blue is added coloring with no flavor of its own. Pour it next to a plain white curaçao and the difference is almost entirely visual. Bear that in mind before you pay extra for the color.

You can, and the result is close. One drop of blue food coloring in 22 ml of triple sec gets you there, though the shade tends toward turquoise rather than the deep sapphire of a commercial bottle. Add the coloring to the liqueur first so it disperses evenly.

Yellow, from somewhere. Lemon juice in quantity, a yellow-tinted soda or a splash of pineapple will all shift blue toward green, and the effect is instant. If you want the lagoon color, use a clear lemon-lime soda and hang the lemon slice on the rim rather than dropping it in.

Both, if you're serious about it. The soda alone leaves the drink sweet and slack, since curaçao brings sugar of its own. Ten milliliters of fresh lemon juice added before the soda gives it a spine, and the color survives that small an amount without going green.

A classic Blue Lagoon calls for 45 ml (1.5 oz) Vodka, 22 ml (0.75 oz) Blue curaçao, 90 ml (3 oz) Lemon-lime soda. That single-serve spec scales cleanly — the recipe above converts it to oz and multiplies it for 2–4 drinks.

A standard Blue Lagoon is roughly 15% ABV once mixed (before ice melt softens it further). That makes it about as strong as a glass of wine.

A Blue Lagoon is built directly in the glass over ice — no shaker required. Add the ingredients in order and give it a brief, gentle stir.