Preheat the oven to 375 F/190 C. In a medium bowl, mix together the flour, sugar, salt, and baking powder. Then pour in the milk and mix until well combined. If you like you can add a few pinches of cinnamon and nutmeg to the batter.
Take an 8x11 to 9x13-inch pan and lightly spray the sides with cooking spray. Then melt the butter either in the microwave or on the stovetop and pour it onto the bottom of the pan.
Now pour the cobbler batter right on top of the melted butter. Spread it out as necessary with a spatula, but don't stir or mix it in with the butter.
Evenly sprinkle the fresh blackberries on the top. Follow that up with a few pinches of cinnamon and nutmeg.
Bake in the middle rack position for 35 to 45 minutes until the top is nice and golden brown. Allow it to cool for a few minutes before serving. Serve plain, with a scoop or two of vanilla ice cream, or topped with whipped cream, whatever you like. Enjoy!