Preheat oven to 425 degrees. Add all filling ingredients together in a large bowl and combine. Place into a 13x9 baking dish.
Combine flour, sugars, baking powder, and salt for the cobbler topping. Whisk together until combined. Add cubed butter and break down the butter into the flour with your hands until the butter is in small pea-sized pieces. Add boiling water 1/4 cup at a time and mix together just until combined, being careful not to melt the butter completely. You should still see white pieces of butter through the batter.
Spoon the batter onto the peach mixture and spread to the edges. With a spoon, combine the cinnamon and sugar for the crust. Sprinkle evenly over the top of the cobbler in one layer.
Place baking dish on baking sheet (this will catch any overflowing fruit) and bake cobbler in preheated oven for 30-40 minutes, or until the batter is completely cooked. You can check this by inserting a toothpick and seeing if it comes out clean. If it does, the cobbler is done.
Remove from oven and let cool for 15 minutes to let the center cool slightly and thicken up. Serve alone or with ice cream. Although, I don't think you'll need the ice cream!