Using a hand mixer, cream together the room temperature butter and cream cheese until smooth.
Add the all-purpose flour to the creamed mixture and mix until a smooth dough forms.
Spray three mini muffin pans with cooking spray.
Use a mini cookie scoop to divide the dough evenly into the 36 muffin cups.
Refrigerate the dough-filled pans while preparing the filling.
In a medium bowl, combine brown sugar, melted butter, eggs, maple extract, and finely chopped pecans until well mixed.
Preheat the oven to 350ºF.
Remove one pan from the refrigerator and press the dough into the bottom and up the sides of each cup to form shells.
Fill each dough shell about two-thirds full with the pecan filling.
Top each filled cup with one pecan half.
Bake the tassies for 18 minutes or until golden brown on top.
Allow the tassies to cool, then carefully loosen with a knife and transfer to a cooling rack.