Preheat the oven to 375 degrees F. Spray a 9-inch pie plate with nonstick spray (not a deep dish).
PREPARE THE BERRIES:
In a medium bowl, toss together the berries, sugar and juice. Put the berry mixture into the prepared dish.
PREPARE THE COBBLER:
In a separate medium bowl, use an electric mixer to combine the butter and sugar; beat until light and fluffy. Mix in the egg and vanilla. Add flour, baking powder and salt, beating just until combined. Drop the batter by the spoonful on top of the berry mixture- covering as much of the top as possible with the batter.
Bake 35 to 40 minutes or until the top is golden brown and the filling is bubbling. Let cool for a few minutes before serving. Serve in dishes with a scoop of ice cream on top (if desired).