In a 10 inch cast iron skillet, heat 2 TB of butter over medium heat. Add the peaches, sugar, lemon juice, vanilla, ginger, salt. Stir and cook the peaches until bubbly, about 5 minutes.
Stir the cornstarch in a small bowl with a spoon of water. When blended, stir into the peach mixture well. Reduce heat to low and cook and stir for another 5 minutes.
While the peaches are cooking, prepare the biscuit topping.
In a large bowl, stir together the flour, salt, baking powder, baking soda and brown sugar. Using a fork or pastry cutter, cut the butter into the flour mixture until the mixture has a crumbly texture.
Work quickly so the butter does not get soft.
Stir in the buttermilk until the dough forms. Spoon over the peaches in the skillet.
Bake in the oven for 20 minutes. Remove from the oven and brush the biscuit topping with the reserved peach juice and sprinkle with white sugar. Return to the oven and bake for another 15 - 20 minutes until the biscuits are cooked through.
Stand before serving. Serve warm or at room temperature.