Heat the oven to 200°C.
Place the chicken pieces in a large baking tray.
Cut both the fennel & onion into 8 wedges. Slice the garlic. Scatter these around the chicken.
If using bacon, dice it into 1 cm cubes. Scatter these or the pancetta around the chicken together with the thyme. Drizzle with 2 Tbsp of olive oil and season with salt and pepper.
Cook for 15 minutes, then turn down the oven temperature to 180°C.
Pour the wine into the tray and cook for another 20-25 minutes, until the chicken is golden and the fennel is tender.
Serve warm with the cooking juices spooned over the chicken and fennel.