Stir together butter, eggs, and brownie mix until just combined.
Pour batter into prepared baking dish and spread evenly.
Bake for 20-25 minutes or until the top is dry and a toothpick inserted into the center comes out clean.
When the brownies come out of the oven, immediately top with your favorite Halloween candies. We recommend candy corn, candy pumpkins, M&Ms, Reese’s pieces, and candy eyes for a silly-spooky twist!