Pre-heat oven to 210°C, dry heat. Place celery, carrots, onions, and garlic and oil in a gastronome tray. Place short ribs, bone side down fat side up. Transfer to the oven, cook for 10 minutes. Remove the tray from oven and add tomato passata, brown sugar, red wine vinegar and beef stock.
Turn ribs to bone side up cover with baking paper and aluminium foil. Please into the oven at 90°C, 60% steam 40% dry heat for 10-12 hours.
Remove from the oven. Turn the beef ribs back over, so the bone side is down and cook at 160°C for 10-15 mins to caramelise. Allow ribs to rest for 20 minutes.
Take the bone out of the short rib and slice.
To assemble the sandwich, take the lightly toasted ciabatta, top with English spinach, tomatoes, sliced beef rib, cheese sauce and caramelised onions. Serve with kipfler potatoes.
