Preheat oven to 180ºC.
Season beef ribs with sea salt and ground pepper. Dust the ribs evenly with flour, and shake any excess off.
Heat some olive oil in a heavy-based casserole dish over high heat and brown ribs for 2- 3 minutes.
Transfer to a tray.
Cook in the oven for 95 minutes per kg.
Pour off half the oil then return the casserole dish to heat and add an onion, and a stalk of celery all finely chopped, and stir for 8 to 10 minutes until caramelised. Stir in 2 tbsp of tomato paste and reduce heat to medium and cook for 4 -5 minutes until dark red in colour.
Return ribs to the casserole dish and bake covered until ribs are tender – about 2 hours).