What technique is used to make an "in and out" martini?

The technique used to make an "in and out" martini is to swirl vermouth and dump. This method involves adding a small amount of vermouth to the mixing glass, swirling it around to coat the inner surfaces, and then dumping out the excess vermouth, leaving just a light film in the glass. This provides a hint of vermouth flavor without overwhelming the drink and allows the gin or vodka to be the star of the cocktail.

This technique is particularly suited for an "in and out" martini, as the focus is on maintaining the spirit's profile while still incorporating the aromatic qualities of the vermouth. Other methods, such as shaking and straining or muddling, would not achieve the same light and delicate balance that characterizes this specific style of martini.