Perennial Virant's Matty Eggleston challenged Stephen Cole, formerly of the Violet Hour (he's planning to open a bar called the Barrelhouse Flat in Lincoln Park in October) with cream of tartar. Cole decided to use the acidic salt to create a chemical reaction with baking powder—he originally wanted to make a version of Pop Rocks, but when that didn't work he moved on to a powder that fizzes in your mouth.
The Boston G
1½ oz Siete Leguas tequila blanco
½ oz Luxardo Maraschino liqueur
½ oz lime juice
¼ t cream of tartar
¼ oz simple syrup
2 dashes Regan's orange bitters
½ t baking soda
Rim glass with chartreuse fizzy powder* and place baking soda in glass. Combine all other ingredients in a shaker with ice, shake, strain, and pour into glass. Top with a few dashes of Elixir Vegetal (or another chartreuse).
*Chartreuse Fizzy Powder
¾ cup green chartreuse
2 cups sugar
¼ cup water
1 T baking soda
¼ cup cream of tartar
Add the first three ingredients to a saucepan, heat over medium heat to hard-crack stage on a candy thermometer (be very careful, as the mixture will be extremely hot). Remove from heat and pour carefully into a mixing bowl. Whisk in the baking soda and cream of tartar, then cool in a dry location. Once cooled, process in a food processor to make into powder.
Cole has challenged Paul McGee of the Whistler with beef stock.