Preheat oven to 350 degrees.
In a small bowl, whisk together oil, honey, rosemary, cayenne, pepper, and salt. Place the walnuts into a mixing bowl and drizzle the oil and spice mixture over the walnuts. Stir to toss and coat the nuts well.
Spread the walnuts in a single layer on a rimmed baking sheet. Bake for 10-15 minutes, or until fragrant, hot, and golden.
Serve nuts warm or at room temperature. Store in an airtight container.