Preheat oven to 350°F
Spray a large rimmed baking sheet generously with nonstick. (or grease with oil)
In a large bowl, combine the walnuts and maple syrup. Gently toss for 1-2 minutes to ensure each piece is coated evenly.
Spread out in an even layer onto prepared baking sheet.
Bake 13-15 minutes or until syrup becomes thick and sticky. Stir 2-3 times while baking.
Remove and transfer to parchment or wax paper in a flat, even layer. (any nuts that are touching may stick together when cooled) Immediately sprinkle with salt.
Let cool at least 5 minutes before eating.
Once completely cooled, store in an airtight container.