Lamb: Season the lamb on all sides with salt and pepper.
Add the olive oil to a large pot, rondeau, or Dutch oven over medium-high heat and sear the lamb until golden brown on all 5 sides, which takes about 3-4 minutes per side. Once brown remove them from the pot and set aside.
Next, add the onions, carrots, celery, turnip, parsnip, and garlic into the pot and brown well, which takes about 10 minutes while stirring occasionally.
Deglaze with the red wine and cook until the amount of liquid is reduced by one half.
Add in the tomato paste and stir until combined and cook for a further 1 to 2 minutes.
Add in the stock followed up by adding in the parsley, thyme, rosemary, salt, and pepper, and mix until combined.
Next, add back in the lamb shanks, place a lid over the pot and cook in the oven at 350° for 2 to 2 1/2 hours.
Remove the lamb from the pot and strain the vegetables. Cook the remaining liquid over high heat for 4 to 5 minutes or until it thickens up a touch more.
Serve the lamb shanks with optional risotto and pour some of the sauce over the top.
Notes
Make-Ahead: This is meant to be eaten once it is finished cooking, however, you can keep it warm over very low simmering heat for up to 1 hour before serving.How to Store: Cover and store the lamb in the sauce in the refrigerator for 3-4 days. You can cover it and freeze it for up to 3 months. Thaw in the refrigerator for 1 day before reheating.How to Reheat: Add the desired number of lamb shanks to a rondeau or saucepot along with some of the sauce and cover and heat in the oven at 350° for 20-25 minutes or until hot.