Line a rimmed baking sheet with parchment paper and set aside.
Mix water, brown sugar, cinnamon, salt and vanilla together.
Heat a small saucepan to medium heat. Add the pecans and stir occasionally until they become fragrant, about 5 minutes.
Pour in the cinnamon sugar mixture and stir to coat. Remove from heat.
Spread the coated pecans in a single layer on the prepared pan.
Cool at room temperature. The pecans will harden in a few hours.
Brown Monk fruit sweetener can be substituted.
When coating your pecans in the saucepan, be sure to stir constantly just until the brown sugar is dissolved. Be careful not to leave them in the pan for too long.
Don’t forget to have your cookie sheet ready. When the pecans come out of the pan, they need to go straight onto the parchment paper and cookie sheet. If you forget this step, you can risk burning them.