Step: 1
Begin by cutting the vanilla and placing it together with the tonka beans inside a container. Pour hot water over the top and add the sugar. Stir the mixture until the sugar is fully dissolved.
Step: 2
Allow the syrup to sit for one day, giving the flavors time to meld together.
Step: 3
After a day has passed, remove the vanilla and tonka beans from the syrup, which should now be chilled. Mix the syrup with blueberry puree, and transfer the mixture into a clean, airtight container.
By following these steps, you should end up with a delicious syrup that can be used to add a sweet, fruity flavor to a variety of drinks and desserts. Enjoy!