Preheat oven to 425F / 220C / 200fan.
Season the chicken wings with salt and pepper. Place on parchment lined baking tray with the garlic (drizzled in a little oil) and roast for about 1 hour, or until golden. Cooking times of the wings will depend on the size of them, should be done in about 35-45 minutes. Remove the garlic after 30 minutes.
Add the wings, garlic, carrots, celery, herbs, onion, and water to a large Dutch oven or stock pot. Bring to boil then simmer for 2 hours until nice and fragrant. Remove the wings, allow to cool and shred the meat for another recipe. (You can place this back on a baking tray to crisp up if you like for tacos.)
Strain the remaining stock by smashing up the veggies and pushing through all the goodness of the veggies juices into the stock. Allow the stock to cool and skim off any fat. If baking before the big day place in the fridge. If making way in advance, place in a ziplock bag in the freezer. Then defrost day before or defrost in microwave on the day. You should have about 4 cups of stock left.