In a flameproof casserole or dutch oven heat the cooking oil over a moderate heat and brown the veal loin on all sides, turning frequently. Add the onions, carrots, celery, tomatoes, baby artichokes and bouquet garni. Reduce the heat, cover, and cook for 1 1/4 hours, turning the meat over occasionally. Stir in the peas and a 1/4 cup of water and simmer for 15 minutes longer. Transfer the meat to a warmed serving platter and arrange the cooked vegetables around it. Strain the cooking liquid into a saucepan and bring it to a boil. Remove saucepan from heat and whisk in the butter, a little at a time.
