Peel your peaches with a peeler, remove pits, and cut into 1/2 inch slices.
In a medium bowl, combine all of the filling ingredients and toss to combine.
Transfer the peach mixture to a 9 inch pie dish (deep dishes are best). Line a baking sheet with foil (to help with anything that spills over) and put the pie dish on the foil lined sheet. Cover the peach mixture in the pie dish with another piece of foil. Set aside.
Make the biscuit mixture my whisking together the flour, sugar, baking soda, baking powder, salt, and cinnamon.
In a small bowl, combine the cold milk with the warm melted butter. Stir the buttermilk and butter until small clumps form. Add the milk mixture to the dry ingredients and stir until just combined.
Scoop out the dough into 8 biscuits on a silicone baking sheet. Bake until they are just starting to brown on the bottom, approximately 10 minutes. Remove and set aside.
Place the foil covered peach mixture in the oven and bake until the peaches are releasing juice, approximately 20 minutes (you can fit both the first round of biscuit baking above and this step in the oven at the same time).
Remove the peach mixture from the oven and remove the foil. Place the biscuits on top and bake until the biscuits are golden brown, approximately 10-15 minutes. If not all of the biscuits fit in the dish, finish cooking the remaining biscuits on the silicone lined baking sheet. Serve warm.
For a sweeter cobbler, use up to 2/3 cup sugar in the filling.This can easily be made in advance. I like to stop before the second bake in step 8, and complete that final step when I am ready to serve.