Mix butter, brown sugar, sugar and egg together until blended. Stir in flour, baking soda and salt. Add Reese's Pieces. Mix well.
Scoop batter into mini muffin pan. (About ¾ full.)
Bake for 8 minutes or until lightly brown and firm in the middle.
Let cool.
Melt 10 orange melts according to package directions. Pipe orange decoration using Wilton star tip. (Or just scoop a little onto the cookie using a spoon.)
Melt 10 Hershey Melts. Using a spoon, drizzle melted chocolate on top of cookies.