Next level roast turkey

Name: Next level roast turkey
Ingredients: 5-6kg oven-ready turkey with the neck, chopped, and giblets included; 150g butter; 3 garlic cloves, finely grated; large handful of mixed herbs such as parsley, thyme or bay, leaves picked and chopped, stalks reserved, plus extra thyme and herbs to serve (optional); 2 lemons, both halved, 1 juiced; 1 onion, roughly chopped; 2 carrots, roughly chopped; 2 tbsp plain flour; 1 tbsp soy sauce; 1 tsp yeast extract; large glass of red wine (about 200ml); 500ml chicken or turkey stock