Preheat oven to 350°F. Lightly coat a mini muffin tin with vegetable cooking spray. Set aside.
Combine the butter and cream cheese in a mixing bowl. Using an electric mixer beat until combined. Add the flour and salt and blend until a soft dough forms.
Working with scant 1 tablespoon of dough (about 13 to 14g) at a time, roll into a ball then press evenly into the bottom and up the sides of each muffin cup. Make sure the dough reaches the top (or slightly over the top) of the pan so you can add a decent amount of filling.
PRO TIP: To make the process easier I use a small cookie scoop to portion the dough and a mini-tart shaper to press the dough into tart shell shapes.
Once filled freeze the muffin tin while preparing the filling. Chilling will help the dough hold its shape when baked.
Stir together the melted butter, sugar and corn syrup until combined. Add the eggs, vanilla and salt. Stir until blended. Fold in the chopped pecans.
Fill each tart shell to the top with about one tablespoon of the filling taking care not to overfill. Bake for 20 to 25 minutes or until the tops are light golden brown. Cool the cookies in the pan for 5 minutes then remove to a cooling rack. Dust with powdered sugar or add a dollop of whipped cream just before serving.
