Preheat Oven : Set oven to 350°F (175°C) and line a baking sheet with parchment paper for easy cleanup.
Prepare Sweet and Spicy Mixture : In a large mixing bowl, whisk together melted butter, honey (or maple syrup), brown sugar, cinnamon, cayenne pepper, sea salt, and vanilla extract until smooth.
Coat Nuts : Add the mixed nuts to the bowl and toss thoroughly so each nut is evenly coated in the sweet and spicy mixture.
Spread on Baking Sheet : Arrange the coated nuts in a single layer on the prepared baking sheet to ensure even roasting.
Roast Nuts : Bake in the preheated oven for 15–20 minutes. Stir the nuts halfway through to prevent burning and promote even caramelization.
Cool Nuts : Remove the baking sheet from the oven and let the nuts cool completely. They will crisp up as they cool.
Serve or Store : Once cooled, serve immediately or store in an airtight container.