Preheat your oven to 200C/440F/Gas 6.
Put the vegetables into a sturdy bottomed roasting tray.
Scatter the herbs and star anise on top.
Lay the bacon on to the veggies and herbs.
Break the chicken wings open and then bash the bones up with the end of a rolling pin to release more of their flavour and then put those into the pan.
Drizzle with olive oil, sprinkle over salt and pepper and toss everything together.
Place the tray into the oven and cook for one hour, or until the meat is tender and falling off the bone.
Take the pan out of the oven and put it on the hob over a low heat, then use a potato masher to really grind and mash everything up as much as you can.
Add the flour and stir until well combined with the vegetable and chicken mash. The longer you leave this all to fry, the darker the gravy will be.
Transfer to a large saucepan and add the boiling water.
Boil for 10 minutes, then reduce the heat and simmer for a further 25 minutes, or until thickened and reduced.
Check for seasoning, and adjust if required.
Place a metal mesh sieve over a bowl and pour the gravy through, mashing everything to get as much flavour as you can from the vegetables, and chicken. Discard the mash once you have sieved all of the gravy.
Cool down for 10 minutes and place in an airtight container in the fridge - use within 3 days.
You can freeze the gravy too - once cooled completely place into a freezer-proof container or bag, and place into freezer.