1/2 oz of Cognac
1/2 oz of Bombay Sapphire gin (or Gin)
1/2 oz of dubonnet french vermouth (or sweet vermouth)
1/2 oz of chartreuse herbal liqueur (or blueberry liqueur)
Pour all ingredients into a cocktail shaker half-filled with ice cubes. Shake and strain into a cocktail glass, and serve.