You need a small'ish cast iron pot to make this in. One that will fit a whole chicken snugly.
Drizzle some olive oil on the chicken. Generously season with salt and pepper. Rub and massage all over the chicken.
Heat the pot on the stove and add a knob of butter. Pleace the chicken in the pot and brown the chicken properly. After a few minutes and the butter has become dark, remove the chicken and discard the butter. Add a fresh nob of butter and continue to brown the chicken. Move the chicken around, on its sides and make sure it's perfectly browned and almost crispy. Remove the chicken and remove the butter. Add new butter and keep on browning.
Remove the chicken and remove the butter.
Add a new knob of butter to the pot.
Peel and smash the garlic and add to the pot. Add the lemon peels and cinnamon. Fry for afew minutes. Add the sage (tear the leaves once). Season with salt and pepper. Fry for a few minutes.
Add the milk and stir a few times. Add the chicken back to the pot in the milk mixture.
Drizzle the juice from half a lemon over the chicken. Place the pot in the oven (without the lid) and roast in the oven for 1.5 hours. Turn the chicken every 30 minutes.
Serve with mashed potatoes and steamed broccoli. Drizzle the sauce and goodness from the pot over the chicken.