What is the word for the gesture when someone takes three fingers and kisses it into the air?
In English, the word used is ‘chef’s kiss’.
From Dictionary.com:
Chef's kiss is a gesture and expression meant to show something is perfect or excellent. The gesture is made by pinching the fingers and thumb of one hand together (often in an OK sign), kissing them, and then tossing them dramatically away from the lips. Its tone can be sincere or ironic.
well I will say: 'magnifico!'
If you call it "finger kiss" or "italian finger kiss" just about everyone will know what you're referring to.
If you want to be correct though, it's "al bacio".