Step 1Coat veal in flour; shake off any excess. Heat olive oil in a large flameproof casserole dish over medium-high heat. Add veal and cook until browned on both sides; remove from pan and set aside.
Step 2Add garlic, celery and carrots to dish; cook, stirring, until celery and carrots soften. Add wine and bring to the boil. Stir in tomato paste, tomatoes, stock and thyme; bring to the boil.
Step 3Return reserved veal to dish; cover, reduce heat to low and simmer for 1 1/2 hours. Uncover dish andnd simmer for a further 30 minutes, or until veal starts to fall off the bone.
Step 4Remove veal from dish; cover to keep warm. Bring sauce to the boil; boil for about 10 minutes, or until sauce thickens slightly.
Step 5Meanwhile, bring 3 cups of water to the boil in a medium saucepan. Add polenta in a thin stream and whisk until smooth. Reduce heat to low and cook, stirring, for 5 minutes, or until thick and hot. Stir in parmesan.
Step 6Blanch beans in a medium saucepan for 2 minutes, or until just tender; drain. Top polenta with veal and sauce; serve with green beans and baby spinach.