How to Make It
Heat the oil in a Dutch oven or large, deep skillet over medium-high heat. Season the chicken with 1 teaspoon each salt and pepper. Cook, skin-side down, until golden brown, 8 to 10 minutes. Transfer to a plate.
Add the leeks and garlic to the Dutch oven. Cook over medium heat, stirring often, until the leeks are just tender, 6 to 8 minutes. Add the broth and sour cream and bring to a simmer. Add the chicken, skin-side up, and simmer over medium-low heat until an instant-read thermometer inserted into the thickest piece registers 165° F, 12 to 14 minutes.
Stir the beans, peas, lemon juice, and chopped dill into the sauce and simmer until the beans are hot, 2 to 3 minutes. Serve topped with dill sprigs.