You need a 12"-16" Dutch Oven.  There are two methods to cook cobbler: 1) coat the oven in butter, or 2) put a lining of aluminum foil in the oven, before adding contents.  The contents of the oven should be

1x - cans of crushed pinapple

2x - cans of apple pie filling

In other words, use twice as much apple as pineapple.  Add the cans of fruit to the oven and mix completely.  On top of the fruit, empty a box of Betty Crocker Deluxe White Cake Mix.  If you like, you can coat the oven with butter before adding contents, put some butter on top of the fruit, and on top of the cake mix.  Bake the cobbler until filling is bubbly and cake mix has baked to a golden brown.