Pre-heat oven to 160 degrees
In pot on high heat add olive oil then osso buco, brown evenly. Then remove and place to one side.
In the same pot, add onion, celery, carrot, and remaining marinade. Cook until tender and caramelised, then add red wine and cook until almost dry.
Add tomatoes and tomato paste and then put into oven proof dish with osso buco and add stock to cover bone.
Place in oven for 4 hours until osso buco is falling off the bone.
Remove meat, strain liquid and reduce.