This simple toasted walnut snack recipe is great for entertaining or an on-the-go snack you can enjoy anytime.
Preheat oven to 300°F. Melt butter in a small saucepan; stir in rosemary, pepper and salt. Add walnuts and stir well with a rubber scraper until mixture evenly coats walnuts.
Transfer to a baking sheet and cook for 30 minutes, stirring every 10 minutes. Let cool completely before storing in an airtight container.
Place butter in the basket of an air fryer (without using a rack). Air fry at 300°F for 2 minutes to melt. Stir in rosemary, pepper and salt. Add walnuts and stir well with a rubber scraper until mixture evenly coats walnuts.
Air fry at 300°F for 5 minutes. Stir well and cook for 2 minutes more. Let cool completely, stirring occasionally. Store in an airtight container.