To make freezer bag: In a gallon size zip-top bag, combine the chicken, salsa, drained beans, corn, scallions, taco seasoning mix, and optional jalapeño. Place in freezer for up to 3 months. Tips: Recipe can be multiplied easily to make as many freezer bags as desired. The freezer bags store more efficiently and thaw more quickly if frozen flat. To cook: If frozen, thaw the freezer bag overnight in the refrigerator, and then transfer the contents of the bag to a slow cooker. (Hint: Swish out the contents of the bag with a few tablespoons of water and add that to the cooker to make use of all the salsa and spices.) If cooking immediately, simply place the ingredients (chicken through optional jalapeño) in the slow cooker. Cover and cook on low heat for 4-6 hours (or 2-3 hours on high heat) or until the chicken is cooked through and tender enough to be pulled apart easily with two forks. At this point, remove the chicken to a plate and shred with two forks and then return it to the slow cooker.