Pour the heavy cream into a large bowl.
Whisk or beat the mixture until it thickens into a cloudy texture.
Slowly add the milk, sugar, and vanilla syrup into the bowl while slowly whisking.
Continue whisking for another half a minute until it takes a soft, cloudy texture.
Your sweet vanilla cold foam’s ready! Use ¼ – ½ cup foam per cup of coffee.
Store mixture in a jar for up to a week, pour into another cup, and whisk until it’s ready to use.