L'Orangerie

Chill an Old Fashioned glass by filling it with ice.

In a mixing glass, add the dry vermouth, triple sec, and the listed drops of Angostura bitters.

Stir the mixture until well-chilled and properly diluted.

Discard the ice from the Old Fashioned glass and strain the cocktail over fresh ice in the glass.

Garnish with a twist of orange to enhance the aroma and presentation.