Preheat oven to 350 F. Spray mini muffin tin with nonstick cooking spray.

In large bowl, whisk melted butter, oil and sugar until well combined. Add eggs and vanilla extract; beat until mixture is thick and pale in color, about 1 minute.

Sift in flour and cocoa powder. Add espresso powder, if desired, and salt. Using rubber spatula, fold dry ingredients into butter mixture until just combined. Batter should be thick.

Using 1-tablespoon cookie scoop, transfer batter to prepared mini muffin tin. Bake 13-15 minutes until toothpick inserted in center comes out mostly clean, with some lingering crumbs.

Add chocolate chips to heat-proof bowl; microwave until smooth and melted. Pour melted chocolate into sandwich bag and cut off small portion of one corner to use as tip. Use melted chocolate to "glue" on pecan antlers, candy eyeballs and red candy noses to brownies.

Allow chocolate to set before transferring brownies to airtight container.