In a large bowl, add the flour, salt and butter. Use a pastry blender in an up and down motion to blend the ingredients together until the mixture looks like crumbs with lumps the size of peas and almonds. These lumps will make your crust flaky. If you don't have a pastry blender, you can combine the ingredients by using clean hands to mash the ingredients together.
Sprinkle 1/2 cup ice water over the mixture and stir lightly with a fork. Squeeze a handful of dough to see if it holds together. Mix in more water as needed. Divide the dough in half and form each half into a chubby disc about 5-inches in diameter. Wrap each in plastic wrap and chill for about an hour.
PREPARE THE CRANBERRY FILLING:
Place 3 cups of the cranberries in a food processor and pulse until they are slightly chopped. In a medium bowl, place the chopped and remaining whole cranberries, sugar, cornstarch, nutmeg, salt, liqueur and mix well.
Roll out one disc of the chilled pie dough to an 11-inch diameter. Place it in a 9-inch regular-depth pie plate. Trim edges to 1/2-inch over the edge of the plate. Tuck the edges under to the edge of the pie plate. Pour the cranberry filling into the unbaked pie crust and dot the little pieces of butter all over the top.
Roll out the second disc of dough and place it on top of the fruit. Trim the edges, crimp and cut vents on top. Alternately, you can cut strips and make a lattice top. Chill the pie for one hour before baking.
BAKE THE PIE:
Preheat the oven to 375 degrees F. Lightly brush some of the egg wash over the entire pie, including the edges.
Bake for 30 minutes. Then pull the pie out of the oven and sprinkle sugar on top. Bake until the crust is just golden, or until you see bubbling coming out between the vents- about 10 more minutes. Remove the pie from the oven, and let it cool completely.
Notes
NUT ADD-IN OPTION: Add in 1/2 cup chopped walnuts to the cranberry mixture, if desired.