To create the marshmallow cold foam, mix one tablespoon of toasted marshmallow syrup, one tablespoon of milk, and three tablespoons of heavy cream in a bowl. Use a frother to whip the mixture for about 15 seconds until it thickens but remains soft.
In a glass, combine two teaspoons of instant espresso for a double shot with one tablespoon of brown sugar, a dash of cinnamon, a pinch of salt, and one tablespoon of toasted marshmallow syrup.
Pour in two ounces of hot water and whisk the mixture until everything is well dissolved.
Fill the glass about three-quarters full with ice, then add approximately half a cup of milk, leaving space for the cold foam.
Finally, pour the toasted marshmallow cold foam over the top of the drink and sprinkle a little extra dash of cinnamon for garnish.
