01 - Preheat oven to 350°F. Line a baking sheet with parchment paper.
02 - In a mixing bowl, combine maple syrup, cinnamon, salt, and vanilla extract if using.
03 - Add the walnuts and toss until thoroughly coated in the maple cinnamon mixture.
04 - Spread the walnuts in a single layer on the prepared baking sheet.
05 - Bake for 12 to 15 minutes, stirring once halfway through, until walnuts are glossy and fragrant.
06 - Remove from oven and let cool completely. The glaze will harden as the walnuts cool.
07 - Store in an airtight container at room temperature for up to 1 week.