In a medium bowl, combine the flour, sugar, salt, and cold butter. ‘Cut’ in the butter using a pastry cutter or your fingers until the butter is the size of peas.
In a measuring cup, mix 2 tablespoons of ice water with vinegar. Add to the dough mixture and stir until you have a rough dough. If dry, add more ice water, 1 teaspoon at a time. Squeeze the dough to ensure it holds together.
Form the dough into a ball, flatten it into a disc, wrap it tightly in plastic wrap, and refrigerate for at least 30 minutes.
Preheat the oven to 425°F (220°C) and position the rack in the middle.
Lightly flour your work surface. Roll the chilled dough into a rectangle, fold it like a business letter into thirds, roll again, then fold once more. Roll the dough into a 9×9-inch square and cut it into 4 equal pieces.
Place the pastry squares on a baking sheet. Fold up the edges of each square about 1/4 inch to form a border. Add 2 slices of cream cheese to the center of each pastry.
Drizzle a small amount of the honey mixture over the cream cheese. Arrange the peach slices on top of each tart.
Brush the edges of the dough with heavy cream and sprinkle generously with cinnamon sugar. Drizzle more honey mixture over the tarts.
Bake for 18-22 minutes until the tarts are golden brown. Let them cool slightly on a wire rack and drizzle with more honey before serving. Enjoy warm!