01 - Set oven temperature to 350°F and prepare a large baking sheet lined with parchment paper.
02 - Place all nuts into a large mixing bowl.
03 - Drizzle olive oil over the nuts and toss to ensure even coating.
04 - Sprinkle sea salt, smoked paprika, black pepper, garlic powder, cayenne pepper, and rosemary if using, then toss thoroughly.
05 - Spread the seasoned nuts in a single layer on the lined baking sheet.
06 - Bake for 18 to 20 minutes, stirring once halfway through, until nuts are golden and aromatic.
07 - Remove from oven and allow to cool completely on the baking sheet to enable crisping.
08 - Transfer cooled nuts to an airtight container and keep at room temperature for up to two weeks.