A homemade toasted marshmallow syrup made with toasted marshmallows, sugar, water, and vanilla. Use it in iced coffee and other homemade coffee drinks.
Toast the marshmallows using an air fryer, oven broiler, or a kitchen torch. Toast until golden brown with some darker spots. I toast mine in my air fryer for about 4 minutes at 350℉ (175℃). Set aside.
Add the sugar and water to a medium saucepan. Heat over medium-high heat, whisking often, for about 5 minutes, until the sugar has completely dissolved and the mixture comes to a boil.
Add the toasted marshmallows and reduce the heat to medium. Whisk constantly for 2–3 minutes, until the marshmallows have melted into the syrup.
Watch the saucepan closely as the mixture will foam considerably. Reduce the heat or briefly lift the saucepan from the burner if the foam rises too high.
Pour the syrup through a fine-mesh sieve into a clean jar or container.
Stir in the vanilla bean paste or vanilla extract.
Cool completely before covering and refrigerating.
Video
Notes
Toasting the marshmallows: You want a lot of golden-brown color with some darker toasted spots. This creates the toasted marshmallow flavor.Mini marshmallows: Use about 1½ cups of mini marshmallows in place of the large marshmallows. They brown very quickly, so watch them carefully while toasting.Storage: Store in an airtight container in the refrigerator. The syrup may thicken slightly when chilled.Using the syrup: Start with 1-2 tablespoons per serving of coffee and add more to taste.