First, prepare the French fries. Slice them and place them in cold water for at least one hour or overnight. The longer the crispier the fries will be.
In the meantime, in a saucepan, melt the butter and add the onions and garlic. Sautee for 2-3 minutes until translucent and starting to colour.
Sprinkle over the flour. Stir and cook over medium heat for 60 seconds to create a light roux.
Pour in the beef and chicken stock, Worcestershire sauce, vinegar, mixed dried herbs, paprika. Stir well and bring to simmer for 2-3 minutes or until the sauce is coating the back of the spoon. Check the seasoning and keep warm aside.
Once ready, preheat a deep fat fryer ( or an air fryer ) to 180˚C/ 350˚F. remove the potato from the water and dry them as much as possible on a clean towel or kitchen paper.
Deep-fry the potatoes until crispy and soft in the centre. Remove from the oil and drain on a kitchen paper for a few minutes adding some salt and pepper.
Warm the gravy and sprinkle some cheddar in the sauce to create a lightly cheesy sauce, Place the fries on a serving dish, add the grated halloumi or cheddar and drizzle over the gravy sauce.
Sprinkle with fresh herbs and enjoy while piping hot.