If your biscuits aren't baked after an hour, chances are your dish was too small or you added too much liquid to the biscuit batter. To avoid this, make sure to use a large enough dish to bake the cobbler, so the biscuits have ample space to expand. Also, your dish should be large enough so the biscuits don't completely cover the entire filling - just like baking a pie, you'll want some air vents in between the topping so the filling can cook and the biscuits can bake through.