Mix softened butter and cream cheese in a bowl until smooth. Blend in flour (a bit at a time), confectioners' sugar and salt. Form dough into a disk. Cover in plastic wrap; refrigerate at least 3 hours. Preheat oven to 325 degrees F. Divide dough into 24 balls; press into two 12-cup mini muffin tins, pushing dough up over edges. Refrigerate.
Mix brown sugar, chocolate, egg, melted butter, vanilla and salt in a bowl until combined. Divide half the pecans among muffin cups; top with brown sugar mixture; sprinkle remaining pecans on top.
Bake 20 minutes or until dough is lightly golden around edges. Let sit 5 minutes. Run tip of knife around cup edges to loosen. Remove when cool enough to handle; transfer to wire racks to cool completely.