Preheat oven to 250F and line a baking sheet with parchment paper.
In a large bowl, whisk together egg whites, water, and vanilla until foamy.
Add cashews and stir to coat in egg whites.
Add brown sugar, granulated sugar, cinnamon, chai spice, and salt. Stir to fully coat.
Spread cashews on baking sheet in a thin layer.
Bake for 40 minutes, stirring every 10 minutes.
Remove from oven and allow to cool completely.