Step 1

Holding a large (preferably 1") cube of ice in the palm of your hand, use the back of a stirring spoon to crack it into large pieces; place in a mixing glass. Repeat with enough ice to fill glass. Add gin and vermouth and, using a bar spoon, rapidly stir 50 times in a circular motion (the outside of the shaker will become very cold and frosty).

Step 2

Strain martini through a Hawthorne strainer (or a large slotted spoon) into a chilled Nick and Nora glass. Strain any excess cocktail into a sidecar set over ice (or a small glass in a bowl of ice).

Step 3

Using a small serrated knife, remove a 1" piece of peel from lemon; it should be stiff enough to provide some resistance (some white pith is okay). Twist peel over drink to express oils, then rub around rim of glass. Float peel, yellow side up, in martini.