Classic Martini

In a mixing glass or cocktail shaker filled with ice cubes, combine 2½ oz. London dry gin and ½ oz. dry vermouth. Stir until well chilled, at least 30 seconds, then strain into chilled martini glass. If garnishing with a green olive, thread olive onto a cocktail pick and gently lower into glass; if garnishing with a lemon peel, pinch the peel over the drink to express its oils, then brush the rim of the glass with the peel and drop peel into glass.