I wanted toasted marshmallow syrup for one very specific reason: s’mores iced coffee.
But I didn’t want to make a batch of homemade marshmallows just to make syrup, and I didn’t want to melt store-bought marshmallows into it and add a whole list of ingredients I hadn’t signed up for.
So this version gets the marshmallow flavor from vanilla and the toasted flavor from caramelized sugar. It tastes like the part of a marshmallow I actually wanted—sweet, vanilla-y and a little toasty—without putting a single marshmallow in the pan.
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why caramelize only part of the sugar?
Caramelizing 175 grams of the sugar gives the syrup its toasted flavor. The remaining 525 grams go in after the water, so the finished syrup stays balanced instead of tasting dark or bitter. You get that browned-sugar edge behind the vanilla, but it still works like a sweet coffee syrup.
a caramel safety lesson i learned the hard way
When water hits hot caramelized sugar, it can steam, bubble and splatter aggressively. I learned that the memorable way: I splashed hot syrup all over myself while trying to stir hardened caramel chunks back into the mixture.
Remove the pan from the heat before adding the hot water. Pour slowly, keep your hands and face back, and give the bubbling time to settle before you do anything else. If some caramel hardens into chunks, that is fixable. Put the pan over low heat and let the pieces dissolve gently instead of trying to win a fight with them and a spoon.
homemade toasted marshmallow coffee syrup
A vanilla-forward coffee syrup with a toasted caramel note—no homemade or store-bought marshmallows required.
ingredients
- 700 g white cane sugar, divided
- 350 g hot water
- 1 tablespoon + 2 teaspoons vanilla extract
- ¼ teaspoon fine salt
instructions
- Add 175 g of the sugar to a saucepan. Heat it until the sugar melts and caramelizes to a deep amber color.
- Remove the pan from the heat. Keeping your hands and face back, slowly add the hot water. The mixture will steam and bubble aggressively, so pause and let it settle before continuing.
- If any caramel hardens into chunks, return the pan to low heat and let the pieces dissolve gently. Do not stir them aggressively.
- Add the remaining 525 g sugar. Stir over low heat until the sugar is completely dissolved and the syrup is smooth.
- Remove the pan from the heat. Stir in the vanilla extract and fine salt.
- Let the syrup cool, transfer it to a clean bottle and refrigerate.
safety note: hot caramel can cause serious burns. Use a saucepan with plenty of room for bubbling, add the water slowly with the pan off the heat, and keep your skin away from the steam.
ways to use toasted marshmallow syrup
Use it in iced coffee, hot coffee, lattes, hot chocolate and blended coffee drinks. It’s also the syrup I use in my S’mores iced coffee and toasted marshmallow cold foam. It also makes an easy ice cream topping when you want the flavor of a toasted marshmallow without pulling out the fire pit.
toasted marshmallow cold foam
Add a little syrup to heavy cream and froth until thick and spoonable. Spoon it over iced coffee and adjust the syrup to taste so the foam stays fluffy instead of getting too sweet or thin.
how i store it
I keep this syrup refrigerated in a clean glass bottle. This is a refrigerator syrup, not a shelf-stable canning recipe.
more homemade coffee syrup
For the rest of the homemade s’mores-coffee lineup, try Homemade Graham Cracker Coffee Syrup and Homemade Cinnamon Dolce Syrup.