FOR DOUGH: CREAM BUTTER, CREAM CHEESE and vanilla together in a mixer or processor. Reduce speed to low and add the flour. Mix until just incorporated. Remove the dough, form into three balls and wrap in plastic wrap. Chill one hour before using. Uncooked dough can be frozen up to two months. Freeze uncooked balls of dough or freeze dough in pie tins. Makes three 25 cm pies. FOR FILLING: MIX PECANS AND BUTTER in a small saucepan over medium heat and cook until butter turns a golden color. Remove from heat and set aside. In a mixing bowl combine eggs, corn syrup, molasses, brown sugar and vanilla. Mix until smooth and then mix in the pecans and butter. Pour this filling into the pie crust and sprinkle with the chocolate chips. Place on the middle rack of a preheated 180ºC oven and bake until the center of the pie is set, about 35 to 40 minutes. Remove from the oven and let the pie cool before serving.