Directions

1. Season chicken on both sides with salt and pepper. Heat oil in a large Dutch oven over medium-high heat. Working in batches if needed, sear chicken, skin-side down, until deeply golden brown, 8-10 minutes. Flip chicken and continue to cook until it is browned on the other side, another 5-8 minutes. Transfer chicken to a large plate, and pour off all fat into a bowl to reserve.
   
2. Return 2 tablespoons of reserved fat to the pot. Add onions, celery, and half the carrots. Season with salt and pepper and cook on medium heat, stirring to scrape up all the bits on the bottom of the pot. Cook until vegetables start to soften, about 4 minutes.
   
3. Return chicken to the pot along with thyme and 8 cups of water. Simmer, uncovered, until chicken is completely tender and liquid has reduced by about 1/4, about 30-40 minutes.
   
4. Transfer chicken to a plate. Remove and discard the skin and bones from the chicken and shred. Strain the stock, you should have about 5 cups; if you have less, you can add water to make up the difference. Heat remaining 3 tablespoons chicken fat along with 1 tablespoon butter (add more butter if not enough chicken fat) over medium heat. Sprinkle in 1/4 cup flour and stir constantly until it’s all a pale golden brown, about 2-3 minutes. Slowly whisk in reserved chicken stock until no lumps remain and bring to a boil.
   
5. Add leeks and remaining carrots, season with salt and pepper and lower the heat to simmer. Add chicken to the pot. Cook, stirring occasionally, until liquid is nicely thickened and carrots and leeks are tender, 10-12 minutes.
   
6. In a medium bowl, whisk together 1 1/2 cups flour, baking powder, 3/4 teaspoon salt and 1/4 teaspoon pepper. In a small bowl, whisk together buttermilk and egg and add to dry ingredients, followed by 2 tablespoons butter, melted. Using a spatula, stir just to combine.
   
7. Using a large spoon, drop quarter-size dollops of the dumpling dough into the pot, they should just sit on top, spacing them apart as much as possible. Cover the pot and reduce heat to low. Cook, undisturbed, until the dumplings are puffed and totally cooked through, 18-22 minutes. Test a dumpling by cutting it in half; it should look slightly biscuity, but with no raw bits of dough. If it needs more time, continue to cook.
   
8. Remove lid and sprinkle with parsley. Divide stew among bowls.