To start, combine the white sugar, light brown sugar, filtered water, pumpkin puree, and pumpkin spice blend in a medium saucepan. Set the pan over medium heat and whisk everything together until it begins to simmer gently. Stir occasionally to help dissolve the sugar.

Once the sugar has completely dissolved and the mixture is simmering, continue to let it cook for about 5 minutes. The syrup should begin to thicken slightly as it simmers. After the time has passed, remove the pan from the heat and set it aside.

Let the syrup cool to room temperature. Once it’s cooled, strain the mixture using a fine mesh strainer to remove any solids from the pumpkin puree and spices. Transfer the strained liquid to a clean container for storage.

Store the pumpkin spice syrup in an airtight container in the refrigerator. This syrup will keep for up to three weeks, making it easy to enjoy the flavors of fall throughout the season.