In a small jug, combine the heavy cream, whole milk, pumpkin purée, vanilla syrup, brown sugar, pumpkin pie spice, and salt. Whisk until the pumpkin and sugar are fully dissolved into the dairy. The mixture should be smooth, pale orange-cream, and pourable. If there are pumpkin clumps, the foam will look messy and separate quickly. Whisking thoroughly at this stage, before any frothing begins, is what breaks up the pumpkin purée's natural texture into the surrounding dairy — any lumps left unblended here will carry directly into the frothed foam, disrupting both its texture and its ability to hold together cleanly.

Froth the pumpkin cream using a milk frother, handheld frother, French press, or drink mixer until thick, cold, and softly aerated. It should become dense enough to sit on top of the cold brew but still loose enough to slowly flow into the drink. The foam should be thick and spoonable, not stiff like whipped cream. If it becomes too thick, it sits like a dessert topping instead of behaving like cold foam. Everything must be cold before frothing. Warm cream foams poorly and melts into the coffee too fast. The pumpkin purée's own fibre content actually helps this particular foam hold structure slightly more readily than a plain dairy cold foam would, but that advantage only comes through properly when every component starts fully cold — warmth works against the foam's stability regardless of what's helping to structure it.

Add 10ml vanilla syrup to each glass. Fill each glass generously with ice, then pour in 180ml cold brew coffee per glass. Stir briefly to combine the vanilla syrup with the cold brew. The base should stay dark and strong. Pumpkin cream is rich, so weak coffee gets buried immediately. Given how rich and assertive the pumpkin cream foam is, this coffee base needs real strength to hold its own once the two components are eventually combined — a weaker cold brew simply wouldn't have enough presence to stay noticeable beneath that foam.

Spoon or slowly pour the pumpkin cream cold foam over each glass, dividing it evenly. Let it sit on top as a defined pale pumpkin layer. The foam should float clearly above the dark cold brew, then slowly marble downward at the edges. If it disappears immediately, it was too thin. If it sits like whipped cream, it was over-frothed. That specific target — dense enough to float and hold its shape initially, loose enough to begin marbling downward at the edges over time — is the middle ground to check for rather than assuming automatically, since either extreme moves the presentation away from what this drink is meant to look like.

Dust the top lightly with pumpkin pie spice. Serve immediately without stirring first, then stir before drinking if desired. The finished drink should taste like strong cold brew first, then vanilla, cream, pumpkin, cinnamon, nutmeg, and gentle spice. It should not taste like pumpkin milk with a little coffee hiding underneath. Treat this flavour ordering as a real target, not a loose description — the coffee's own strength should remain the clearly dominant note, with everything else layering in as support rather than taking over.