Line a rimmed baking sheet with parchment paper; spray with cooking spray.

In a medium skillet, bring maple syrup, salt, cumin, and pepper to a boil over medium-high heat. Stir in pistachios; cook, stirring constantly, until pistachios release a nutty aroma and syrup turns a deep-amber color.

Pour syrup mixture onto prepared pan, spreading so nuts are not touching each other. Let cool completely. Store in an airtight container for up to 1 week.