Coat a large baking dish with coconut oil. To the baking dish, add the chicken. Cover and place in the oven. Bake for 20 minutes, until chicken is cooked through and no longer pink in the center. Allow chicken to cool and shred using two forks.
In a large bowl, mix the chicken, and the next 8 ingredients (mushrooms through paprika). Pour the chicken mixture into a large baking dish, top with the nuts and place in the oven. Bake for 15 to 20 minutes, until casserole is hot and bubbling. Serve warm.