First, grease the pot you're using and a plate. Mix sugar, water, cinnamon, and salt in the pan on medium heat. When it gets to a rolling boil, add the walnuts.
Next, mix the nuts with the sugar mixture. Bring it back to a rolling boil.
Then, take the pan of the heat and stir contantly without breaking the nuts. This is when you add the vanilla. When no more sugar mixture pools at the bottom of the pan and the sugar is crystalized, transfer to a greased plate.
Finally, wait for the spiced nuts to cool. This should take about 5 minutes. Enjoy your spiced nuts!