Preheat oven to 375°F.
Bake the sliced bacon on a slotted pan until crisp. Remove to cool then chop.
Place softened cream cheese in a bowl and combine with parsley, thyme, garlic. Transfer half the cream cheese to a food processor to use in the dough. Add bacon to the cream cheese left in the bowl and stir to combine.
To the cream cheese in the food processor bowl, add the flour, a teaspoon of salt and cold, diced butter. Pulse to combine into small crumbles then, with dough setting on, pour ice water through feed tube to form a pastry dough. (I place about 1/4 cup cold water in my cocktail shaker with ice and shake a few times then strain into the dough to make sure water is super cold.) Remove dough to pastry board and turn a few times to form a smooth disc; wrap and refrigerate for 30 minutes.
Heat a very large skillet over medium heat and melt butter, about 2 tablespoons. Add butternut squash and season with salt, pepper and nutmeg. Add leeks and apples, and cook to soften a bit, 10-12 minutes. Add torn sage leaves to the mixture.
Working on parchment paper, roll out dough to a large, round, thin layer. Spread the bacon and herb cheese over the center of the dough, leaving a couple of inches of border. Top the cheese with an even mound of butternut-apple mixture. Fold the dough up and pinch over every few inches to form a galette or rustic-edged crust. Brush with egg or buttermilk and transfer to baking sheet, bake 30 minutes. Add more wash and bake 10 minutes more. Cool a few minutes to set and transfer to serving plate.
Serve with small green salad with cider vinegar dressing alongside.