Who can resist a one-pot roast? Nobody. And there's no reason to. Not only is it super easy, but it's one of the most flavourful ways to cook, because all those rich and earthy flavours – from mushrooms to pan-seared chicken – cosy up together in the pot and become extra good friends. The end result is a deeply delicious dish that makes you feel all warm and fuzzy.
Preheat oven to 200°C fan-forced. Heat an ovenproof dish with a lid over medium heat. Season chicken with salt. Add butter to dish and, when it starts to bubble, add chicken skin-side down. Cook for 5 minutes or until golden brown. While chicken is cooking, continue with step 2.
Cut dark green tops off leek and discard. Halve leek lengthwise and rinse under running water. Slice into half moons. Chop mushrooms into quarters. Pick rosemary leaves from their stems and roughly chop. Peel and crush garlic. Drain and rinse beans.
Once chicken is golden brown, remove from pan and set aside. Add garlic and rosemary and stir for 30 seconds or until fragrant.
Dissolve stock cube in 250ml (1 cup) boiling water. Add mushroom and leek to pan and cook for 3–4 minutes or until starting to soften. Add stock and bring to a simmer.
Return chicken to pan and cover with lid. Transfer to oven and bake for 25 minutes. Carefully remove from oven and remove lid, return dish to oven and bake, uncovered, for a further 15 minutes or until chicken is tender and the skin has crisped.
Roughly chop spinach. Carefully remove the dish from oven. Remove chicken and set aside. Add chopped spinach, cannellini beans and red wine vinegar to dish and stir to combine. Divide between bowls and top with chicken to serve.