Allow the sauce to reduce and thicken over medium heat. Finely chop the mint and thyme and stir them into the gravy.
Just before serving, add 1 tablespoon of red wine vinegar for a final touch of acidity.
To Serve: Serve the tender lamb shanks with the herb-infused gravy, and enjoy over a bed of mashed sweet potatoes for a comforting and flavorful meal.
