Instructions

Place the dried beans in a large bowl and cover them with an inch of water. Soak for 24 hours, or at least overnight — topping up the water if the beans soak it up. Drain the beans and set aside.

Arrange a rack in the middle of the oven and heat to 350°F. Heat the oil in a 4-quart (or larger) Dutch oven or heavy, ovenproof pot over medium heat until shimmering. Add the onion and garlic and cook, stirring frequently, until they are tender and the onion is nearly translucent, 5 to 7 minutes. Add the drained beans and stir to combine. Turn off the heat.

Take a sharp vegetable peeler and carefully peel 1 of the lemons. Peel it in wide strips, taking care that you remove only the top yellow layer of peel — you do not want any of the bitter white pith. Add all the lemon peel to the beans. Juice the lemon, add the juice to the beans, and stir to combine. (Reserve the second lemon for later.)
Pat the chicken dry, and lightly season all over with salt and pepper. Place the chicken on top of the beans. Add water until it covers the beans and comes up to just below the chicken. Lay the thyme sprigs on top. Turn the heat to high and bring the water to a simmer. Cover the pot and put it in the oven.

Bake until the beans are very tender and creamy, about 1 1/2 hours. Check the beans a couple of times throughout and if they are looking dry, add a few splashes of water. The resulting cooked beans should be brothy. Meanwhile, make the mint pesto.
Place all the pesto ingredients in a small food processor or chopper and pulse until finely chopped. Transfer to a serving bowl. If not using immediately, store in the refrigerator with plastic wrap completely covering and touching the surface of the pesto to prevent oxidization.

Uncover the pot and transfer the chicken to a large plate or clean cutting board. Remove the thyme stalks. Finely grate the zest of the remaining lemon, then juice it. Add the zest, juice, and dill fronds to the beans and stir to combine. Taste and season with salt and pepper as needed. Shred or chop the chicken and place it back on top of the beans. Top with the mint pesto and serve.

To serve, scoop up a spoon of beans, and top with chicken. Make sure each serving has a dollop of pesto as well. Serve with a green salad and good bread to soak up the sauce.