2 oz of Gin
1/2 oz of sweet vermouth
1 tsp of white creme de menthe (or Mint liqueur)
1 dash of orange bitters
1/2 oz of dry vermouth
Stir the gin, vermouths, creme de menthe and orange bitters together in a mixing glass half-filled with ice cubes. Strain into a chilled cocktail glass, and serve.