My favorite Christmas pie is adapted from a recipe from Paul Robins.
4 eggs
1 cup sugar 
2/3 light karo syrup
1/3 pure maple syrup
3 T. melted butter
1 and 1/2 t. vanilla
big pinch of salt
1 cup or slightly more pecans, broken
Preheat oven to 300 degrees.  Beat eggs well with a fork.  Add the rest of the ingredients. Pour into an unbaked pie shell and bake for about an hour.  Pie should be just set...no jiggling!
Single Buttery Pie Crust
(For a 9-inch pie plate)
1 1/2 cups flour
1/2 teaspoon salt
1/2 teaspoon sugar
1 stick (8 tablespoons) unsalted butter, very cold, in pieces
2 tablespoons solid shortening, very cold
About 4 tablespoons ice water
Mix flour, salt and sugar. Cut in butter and shortening until mixture resembles flaky meal. Sprinkle in ice water. Work into a ball that cleans the sides of the mixing bowl. Flatten dough into a disk. Wrap with plastic film, and chill 30 minutes (or freeze). Roll dough into a circle 3 to 4 inches wider than pie plate, and trim with scissors so dough extends 3/4 inch below the rim. Fold this overhang under so it is even with plate's rim and crimp into large flutes. Chill 30 minutes.