Heat oven to 180C/160C fan/gas 4.
Mash the butter with the lemon juice,
sage and some seasoning. Gently
separate the skin from the chicken using
your hand – start from the bottom of the
breast, moving round to the legs, and be
careful not to break the skin. Rub the
butter underneath. Season the cavity
and stuff with half the garlic cloves.
Place the potatoes and a few of the
remaining garlic cloves in the base of a
large roasting tray, drizzle with half the
olive oil and place the chicken on top.
Fill each pepper half with a crushed
garlic clove and a quarter of the plum
tomatoes, drizzle with remaining olive oil
and season. Place around the outside of
the chicken and pour over the stock.
Roast for 1 hr 50 mins or until the juices
run clear. Add the courgettes after 1 hr,
tossing them in the oil in the pan. Remove
and allow to rest for 30 mins, then place
the chicken and veg on a serving plate.
Mix the mustard with the red wine
vinegar, olive oil and seasoning. Skim any
excess fat off the cooking juices and
place in a small saucepan. Bring to the
boil then remove from the heat and
whisk in the vinaigrette. Spoon over the
chicken and vegetables, then serve.