Combine ingredients in a small pitcher. Add the heavy cream, milk, and vanilla syrup to a small frothing pitcher or mason jar. Keep everything cold — straight from the fridge works best.
Froth until thick and billowy. Use a handheld milk frother and froth for 20–30 seconds. You're looking for thick, creamy foam that holds its shape but isn't stiff. It should be pourable but structured.
Check the consistency. Tilt the pitcher. The foam should move slowly — like a thick milkshake consistency. If too liquid, froth for another 10 seconds. If stiff and clumping, you've gone slightly too far.
Pour your cold brew or iced coffee. Fill your glass with ice and pour in your cold brew or iced coffee. Leave about an inch of space at the top. Don't have cold brew ready? My How to Make Cold Brew Coffee at Home guide has you covered.
Spoon or pour the cold foam on top. Gently pour or spoon the sweet cream cold foam over the top. It should sit on the surface like a soft cloud. Don't stir — that's the whole point.
Garnish if desired. A light dusting of cinnamon or flavored syrup on top finishes it beautifully.
