Preheat oven to 350 degrees.
Wash grapes and pop out grape pulp/seeds and save in another bowl for juicing. Check to make sure no seeds in the hulls.
Put grape hulls in pot with enough water to almost cover grapes. Amount will depend on size of pot. You can always add more water if needed.
Bring to a boil and cook on high for 20 minutes stirring often. Foam will start to form at the top. Just keep folding it back into the hulls. Then for another 5 minutes turn to medium heat to finish cooking.
Once grape hulls are soft, strain to remove any juice and keep for later. Check carefully to make sure no seeds slipped through.
Put hulls in food processer/blender then chop and process until hulls have a more pudding-like texture.
Spray a 9 x 9 x 2 pan with cooking spray.
Add pureed grape hulls to pan and spread evenly.
Sprinkle the cinnamon and white sugar over the grape hulls, distributing evenly. This is a good time to test for sweetness. If this isn't enough sugar, add until your desired sweetness level is achieved.
Cover with ½ box of dry yellow cake mix. Make sure all of grape mixture is covered.
Melt the unsalted butter and pour over the cake mix evenly.
Cook in oven for approximately 30-35 minutes or until the top is golden brown.
Top with the roasted pecans and serve hot with vanilla ice cream or Cool Whip.