Brew your espresso fresh and keep it hot; the shake is meant to have a warm coffee contrast against the cold gelato.
Add the gelato, milk, 1 shot of espresso, and salt to a blender.
Blend on high for 15-20 seconds until smooth and creamy; do not over-blend since the hot espresso thins it slightly.
Pour into a chilled glass, then pour the second hot espresso shot directly over the top just before serving.
Top with whipped cream and a dusting of cocoa powder, and serve immediately while the espresso is still warm.