1. Soak the beans overnight in a bowl with cold water.
2. Drain the beans, place them in a pot with water, boil for 45 – 50 minutes, then drain again.
3. In a small bowl put the 100 g butter with the mustard, honey, garlic powder, onion powder, nutmeg, lemon zest, salt and freshly ground pepper; whisk until everything is well combined.
4. Spread the butter mixture all over the chicken, adding 2 tsp. of the butter mixture and half the rosemary inside the cavity. Place the chicken in a baking tray.
5. On a cutting board, with a sharp knife, halve the leek and the carrots lengthwise, then slice them thinly.
6. Heat a deep non-stick skillet over high heat until very hot. Add the 2 tbsp. butter and let it melt.
7. Sauté the leek and carrots for 2-3 minutes until they start to soften without browning.
8. Sprinkle over the flour, stir well until no streaks of flour are visible, add the beans, the lemon zest and juice, pour in the chicken stock, season with salt and freshly ground pepper, and bring to a boil.
9. Add the beans to the baking tray with the chicken, add the remaining rosemary, and bake in a preheated oven at 180 °C for 65 – 70 minutes. When the chicken is ready, remove the tray from the oven and serve in the center of the table.
