http://www.bonappetit.com/recipe/thyme-roasted-walnuts
Preheat oven to 350°. Toss walnuts, oil, thyme, and salt on a rimmed baking sheet until salt and thyme are evenly distributed. Bake until walnuts are golden brown and fragrant, 10–15 minutes.
Walnuts can be made 8 hours ahead. Store in an airtight container at room temperature.