Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the maple syrup, ground cinnamon, vanilla extract, salt, and cayenne pepper. Mix well until all the ingredients are incorporated.
Add the pecan halves to the bowl and toss them until they're evenly coated with the maple mixture.
Spread the coated pecans in a single layer on the prepared baking sheet.
Roast the pecans in the preheated oven for about 10-12 minutes, stirring halfway through to ensure even roasting. Keep an eye on them to prevent burning; they should be golden and fragrant.
Once done, remove the baking sheet from the oven and allow the pecans to cool completely on the sheet. They will become crunchy as they cool.
Once cooled, break apart any clusters, and store in an airtight container.
Notes
Serve in a decorative bowl or package in mason jars as gifts.