Preheat the oven to 375 degrees F.
Place the nuts on a parchment paper lined baking sheet and bake for about 10 minutes until they are warmed through and slightly browned.
Meanwhile, in a pot over medium heat, combine the rosemary, cayenne pepper, sugar, salt, and butter and whisk until well incorporated.
Toss the warm nuts with the rosemary mixture until the nuts are completely coated.
Serve warm.
***Tip - These nuts are best if served immediately. If they sit for a while, they will get sticky.