Place the quinoa in a fine mesh strainer and rinse under cool water. Add the quinoa and all remaining ingredients except tomato paste and salt and pepper into a 6-quart slow cooker. Cook for 6–7 hours on low or 4–5 hours on high.
Approximately 1 hour before serving, remove chicken breasts and shred into small chunks. Add the tomato paste and shredded chicken back into the slow cooker and stir to dissolve the tomato paste. Allow the chili to cook for the remainder of the hour then season with salt and pepper to taste.
Serve with your favorite toppings, such as grated cheese, sour cream, chopped avocados and tortilla chips.
Notes
Although most quinoa has been pre-rinsed to remove its naturally bitter outer coating, it’s a good idea to rinse it again using a mesh strainer.