1) Add Land O Lakes® Unsalted Butter in Half Sticks to a small pot over low heat. Once melted, allow butter to simmer until a foam forms on top. Then stir slowly. Butter will separate a bit and the solids should sit on the bottom of the pan. After 5-6 minutes of low cooking, the butter should brown slightly and smell very nutty. Remove it from the heat at this point.
2) In a small food processor, pulse vanilla cookies until they are completely broken down. Process walnuts separately.
3) Stir together cookies, nuts and cocoa powder. Then stir in brown butter, honey, and rum flavoring. Mix well to combine.
4) Chill mixture in the freezer for 5-10 minutes until it’s firm. Then make small tablespoon-sized balls out of the mixture. Roll in decorating sugar.
Serve rum balls immediately or store in the fridge for a few days.