Pre-heat the oven to 160°. Add the onion, garlic powder, oregano and stock powder to the softened butter mix well.
Place your hand underneath the chicken skin seperating the skin from the meat carefully so to avoid tearing. Place the garlic butter under the skin and place into the tray.
Add your choice of vegetables to the tray. Season with salt and pepper and a drizzle of olive oil. Add a generous amount of salt and pepper to the skin of the chicken and cover the tray in foil. Cook the chicken for 1½ hours at 160°. Once cooked, remove the foil and turn the oven up to 200°. Cook until golden.