In a small sauce pan over medium heat, combine salt, brown sugar, cider, rosemary, thyme and chili powder. Stir just until sugar and salt dissolve. Let cool completely.
In a large zip-close plastic bag, combine pork loin and brine solution. Squeeze out any air and seal bag shut. Place in a bowl in case of any leaks, then refrigerate for 24 hours.
30 minutes before you are ready to cook, heat oven to 350º. Fit a roasting pan with a rack. Drain pork and discard brine solution. Rinse pork with cool water, then pat it dry with paper towels. Rub surface of pork with oil and place on the rack. Roast for 45 minutes or until a thermometer reads 145º at the centre of the pork. Let rest for 15 minutes before slicing.
Can be used on whole chicken. Soak in brine for only 4 hours, not 24. Cooking time depends on how large the chicken is. Just cook until the internal temperature of the meat is 160º