Cut the butter into 1/2" cubes wrap in plastic wrap and refrigerate for a minimum of half an hour.
Place the flour, salt and baking powder in a bowl and refrigerate for a minimum of half an hour.
Place the flour in a food processor and pulse for a few seconds.
Add the butter and pulse until the butter is the size of small peas.
Add the lowest amount of ice water and vinegar and pulse about 5 times. Pinch a small amount of mixture with your fingers, if it does not hold together add the remaining of the ice water and pulse again.
(The mixture should not hold together unless being pinched)
Place the mixture in a medium bowl (or a plastic bag) and using your fingers pinch it together to form a disc.
Wrap the disc in a plastic wrap and allow to chill for a minimum of 1 hour (or overnight)
After the dough had chilled, roll it into a 12" circle and place it in a 9" pie dish.
Fold in the access dough and create your choice of pattern or cut the access. Place the pie dish in the refrigerator until time to bake.
Place all the ingredients in a large bowl and gently stir to distribute.
Let sit for 45-60 minutes.
Place the ingredients in a medium bowl and rub it all using your fingers until you get a moist mixture. Place in the refrigerator.
Preheat oven to 425F and place a large cookie sheet lined with parchment paper at the bottom rack of the oven.
Remove the pie shell from the refrigerator and brush it with the egg white. (including the edges)
Evenly spread 1 TBS of almond flour on the crust then add the filling.
Sprinkle half the amount of the streusel.
Bake the pie for 15 minutes.
25 minutes into the baking, remove the pie and sprinkle the streusel on top of the pie. Return the pie to the oven.
Lower the oven temperature to 400F and continue baking for 40-45 minutes longer. Or until you notice some bubbles.
Allow the pie to completely cool before slicing.