Step 1
Preheat the oven to 175°C (350°F).
Step 2
Pour the melted butter into the bottom of an 20x20 cm (8-inch) square baking pan. In a bowl, mix together the sugar, self-rising flour, and milk until just combined, then pour the batter over the melted butter without stirring. Spread the fresh blackberries evenly over the batter.
Step 3
Bake in the preheated oven until the top is golden brown and the cobbler is bubbling, about 45 minutes.