Preheat the oven to 400˚F
Place about 1/2 cup of flour on a plate and dredge the veal.
Heat the oil in a large oven-safe pot with a fitted lid (I use a 12-cup Le Crueset pot).
Brown the veal shanks, about 5 minutes on one side, then add the garlic cloves.
Brown the shanks for about 5 minutes on the other side, then add the onion, carrot, basil, salt and pepper to taste.
Continue browning the shanks, cooking until the onions are soft, about 5 minutes more.
Add the wine, lower the heat to low and cook for 10 minutes, until the wine evaporates, then add the tomatoes and butter.
Cover and simmer the osso bucco for a few minutes to meld the flavors, and then place the pot in the oven. Cook for 30 minutes.
Remove the pot and add the mushrooms.
Lower the heat to 350˚F and return the pot to the oven.
Cook for another 30 minutes until the shanks are meltingly tender.
In the meantime, prepare the gremolada. Combine all the ingredients in a small bowl.
Remove the shanks and serve garnished with the gremolada.