Season the veal generously with salt and pepper. Drizzle with oil and rub the onion soup mix and rosemary all over the sides of the roast. Set aside.

Preheat oven to 350 degrees Fahrenheit. In a large frying pan over medium-high heat, warm the canola oil. Add the onions and mushrooms, sautéing over medium-high heat until softened and lightly browned, about eight to 10 minutes.

Pour the wine and water into a large roasting pan. Add the veal and pour the mushrooms and onions over the top. Cover tightly with foil. Bake for three and a half to four hours or until meat is very soft when inserting a fork in the center of the roast.

Allow to cool and then place in the refrigerator overnight, or until meat is cold and firm. Transfer the veal to a cutting board. Using an electric or sharp knife and working against the grain, cut the veal into thin slices. Place the veal back into the pan and into the gravy. Veal can be frozen at this point and reheated before serving.

Arrange the slices on a platter and surround with the mushrooms and onions. Spoon the cooking juices over the top.