Ossobuco is one of my favorite things to make for special occasions that's different from your typical ham or turkey dinner. I've made this for numerous Sunday dinners with friends, and it's always a huge hit. :)
I know it looks a bit daunting, but I promise it's not nearly as difficult as it might seem to be. It's delicious, and a great go-to dinner.
In a large pot or dutch oven on medium heat, heat your oil and 1 Tbsp of butter together. Tie your shanks with some kitchen twine to help keep their shape, season your veal shanks well, and dredge them in your flour. (Make sure to shake off excess flour.) Put into your pot, and sear on both sides until they are nice and golden brown. (NOTE: Be sure to watch the meat carefully. You don't want it to get too high because then the seasonings and the outsides of the shanks will burn.)
Once all the shanks have been seared to a lovely golden brown color, remove from pot and set aside. With the pot still on medium, add in the other Tbsp of butter, along with your carrots, celery stalks, and onions. Season with salt to help draw out the moisture from the veggies. Stir and saute the veggies until they become soft and the onions are translucent, about 7-8 minutes.
Add the tomato paste, and stir to incorporate well. Once the tomato paste has been totally mixed in, add in your wine to deglaze your pot. Add in the can of crushed tomatoes, and stir. Add the seared veal shanks back into the same pot. Add in your stock. Put in the bouquet garni (herb pouch), and then bring your osso buco to a boil.
Once the osso buco begins to boil, reduce your heat to low, cover your pot, and simmer for about 2-3 hours, or until the meat is falling off the bone. (NOTE: You'll want to check this about every 15-30 minutes to give it a stir, and to add more stock if needed. You want to be sure that your shanks are almost completely submerged during cooking.)
To make the gremolata, give your parsley a rough chop. Add in your lemon zest and the minced garlic, then chop everything together until it is very fine. Once the ossobuco is done, carefully remove them from the pot, cut off twine and discard. Top with gremolata, and serve. Also, remember to remove the bouquet garni as well. Osso buco is best served with risotto alla milanese, but you can also serve it with mashed potatoes, gnocchi, pasta, and even spaghetti squash.