Preheat oven to 350°. Spray mini muffin tins with cooking spray.

Dough:

In a food processor, pulse the pecans with the sugar, salt and flour, until the pecans are ground up and the ingredients are mixed.

Add in COLD margarine, and pulse until the dough becomes coarse.

Slowly pour in cold water through the feed tube of the processor, pulsing until the dough comes together. Remove the dough from the processor bowl and place on a clean, floured work surface.

Form dough into a ball and divide evenly into 24 pieces. 

Roll each piece into a ball and press into cups of muffin tins, (press evenly until the bottom of each cup is covered). TIP: If the dough is sticky as you work with it, dip your fingers in flour.

Bake 15 to 18 minutes, until crusts are golden. Check every so often to ensure they don't get too brown.

Filling:

In a medium bowl, whisk egg and yolk with dark corn syrup, sugar, pumpkin puree and vanilla. Stir in the chopped pecans.

Remove crusts from oven and place 1 tablespoon of filling into each cup. Top each with 1 pecan half.

Return muffin tins to oven and continue baking for 12-15 minutes, until the filling is set. 

Allow to cool before removing from tins.