For the crust: Measure out all dry ingredients, combine and place in freezer, keep butter & liquid ingredients in refrigerator for at least one hour prior to preparation.
When ready, add dry ingredients to food processor and pulse to mix thoroughly. Add butter cubes and pulse until mixture resembles pea-sized meal. Add vinegar, pulse to mix then add ice water, 1 T at a time, until dough begins to stick together and when pinched by hand, holds together. Remove from processor and transfer to work surface. Divide the dough into two equal parts and gently form into balls, and wrap in waxed paper and refrigerate for at least one hour.
For the filling: Mix all dry ingredients, including vanilla bean seeds together. Add 2 T of this dry mixture to roasting pan, along with peeled and sliced apples. Place under broiler and broil until apples are slightly browned but not cooked through. Once nicely browned, remove and add rest of the ingredients, except butter.
Adding Filling to Pie Dough: Chill pie plate while you roll out 1 of the dough discs on a lightly floured surface until you get a disc that measure slightly larger than your pie plate and about 1/8 “– ¼” thick. Pull out pie plate and gently place rolled out dough in plate.
Add broiled apples mixture, then dot with 4 T butter. Roll out 2nd disc into a circle about 1/8” – ¼” thick and place on top of apples. Pinch top and bottom dough edges together and form a decorative edge.
For the topping: beat the egg and cream together in a small dish then brush top and edges of pie with mixture, sprinkle with sugar.
Bake at 400 F for 45 minutes Cover edges of pie with aluminum foil if starting to brown too quickly. Turn pie in oven and cook an additional 15 minutes or until done. Cool for at least two hours prior to serving.