Peahen the oven to 400 degrees F.
In a bowl, toss and combine the peaches, blueberries, sugars, cornstarch, bourbon and vanilla.
Pour the mixture into a 9 inch cast iron or heavy metal pan.
In another bowl, add the flour, sugar, baking powder, butter. Crumble together until the butter is like sand.
Mix in the milk until the dough comes together and forms a ball.
Dump the dough out onto your floured work surface and pat into a circle about 1 inch thick.
Using a 3 inch circle cutter, cut out 6 pieces of the biscuit dough and set them on top of the fruit mixture.
Using a pastry brush, glaze the biscuits with the remaining milk and then sprinkle liberally with sugar.
Place the cobbler into the oven and bake for about 30-35 minutes and the biscuits are golden brown and well baked underneath.