Preheat oven to 400°F.
For dough: Place flour, salt, baking powder, butter, and cream cheese in a food processor and pulse until a fine meal forms. While pulsing, add water and vinegar and continue to pulse until dough forms. Dump dough onto a clean surface and form into a disc. Tightly cover in plastic wrap and refrigerate for 30 minutes.
Lightly flour a clean surface and roll dough out into a 12”x12” square, about ⅛-¼ inch thick.
Transfer dough onto a parchment lined baking sheet.
For filling: Place all ingredients into a large mixing bowl and toss together.
To assemble: Fill one side of dough with filling, leaving a ½ inch border around the edge. Lightly egg wash perimeter and fold the unfilled side over. Firmly press edges together with a fork and score the top of the pie to allow steam to escape while baking. Brush top with egg wash and sprinkle with sanding sugar.
Bake for 40-45 minutes or until golden brown. Allow pie to cool for 20-30 minutes before cutting and serving.