Preheat the oven to 425F.
In a medium bowl, combine the peeled and sliced peaches, lemon juice, cornstarch, vanilla bean, cinnamon, cardamom and brown sugar. Stir to combine thoroughly.
Place 1/2 cup of the peaches into the center of each dough round, laying the peaches flat and leaving an inch and a half or so around the perimeter of the dough rounds. Reserve the syrup left over from the peaches macerating.
Fold the edges of the dough over, overlapping slightly. Gently press where the dough intersects to help the dough keep it's shape while baking.
Place the galettes into the refrigerator for 30 minutes.
When ready to bake, evenly distribute the reserved syrup over the galettes.
Mix the egg with a tablespoon of milk or cream. Brush the mixture onto the galette edges. Sprinkle the edges with turbinado sugar.
Bake for 23-26 minutes or until the crust has turned golden brown and the filling is bubbling.
Microwave the honey for 10 seconds or heat in a small saucepan until just warmed through and thinned.
Brush the honey over the peaches. Sprinkle the chopped pistachios over the peaches and serve warm or at room temperature.