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. After 10 minutes, remove ribs 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 into oven 90°C, 60% steam 40% dry heat for 10-12 hours.
Remove from the oven and allow ribs to rest for 20 minutes.
Take the bone out of the short rib, cut into slices.
Assemble sandwich. Place Ciabatta roll, toasted and buttered on a board, top with English spinach, tomatoes, sliced beef rib, cheese sauce and caramelised onions, place bread on top. Serve with rustic Kipfler potatoes.