1 of egg
2 oz of Gin
1 tsp of green creme de menthe (or Mint liqueur)
1 tsp of powdered sugar (or sugar)
1/2 of msr tequila (or Agavero Tequila Liqueur)
carbonated water (or sparkling water)
Shake all ingredients (except carbonated water) with ice and strain into a highball glass over 2 ice cubes. Fill with carbonated water, stir, and serve.