In a very large stock pot, add the turkey carcass and all the veggies. Pour in the water and the rice, and bring everything to a boil. Let it simmer for 90 minutes. Use tongs to remove any bones, etc. Season with salt, white pepper, and garnish with scallion and cilantro.
Now, that's the way we've always done it. But if you want a really smooth congee, you can do it a slightly different way. Rather than adding the rice to the pot at the beginning, simply add the carcass, vegetables, and water to the stock pot. Simmer for 2 hours until you have a rich stock. Remove any large bones and then strain the stock into a clean pot. Add the rice, bring to a boil, and simmer for another 90 minutes. Stir in some leftover shredded turkey, season with salt and pepper, and garnish with scallions and cilantro.
Leftover Thanksgiving Turkey Congee by The Woks of Life. Recipe URL: https://thewoksoflife.com/leftover-thanksgiving-turkey-congee/