If you prefer a chillier drink, pop your serving glass in the freezer for a few minutes while you prepare the coffee.
Loosen the pistachio cream: scoop it into a small jar or bowl and add about 1 tablespoon warm milk. Whisk or shake vigorously until it becomes a pourable, glossy syrup.
Pour the pistachio mixture into the bottom of a 12-oz glass and use the back of a spoon to spread it slightly up the sides for an attractive streaked effect.
Combine the remaining cold milk and the vanilla extract in a jar and give it a quick shake (10–15 seconds) to incorporate and create light texture.
Add the ice to the glass over the pistachio layer, then slowly pour the vanilla-flavored milk over the ice to keep some separation for a layered look.
Pour the espresso shot gently over the top so it floats between milk and ice. Leave it layered or stir lightly before drinking to blend the pistachio flavor throughout.
Serve immediately with a straw, and if desired, give it one quick stir to combine the pistachio syrup with the milk and coffee.