Wash and trim the shanks. Wash the shanks and use a sharp knife to remove some of the larger fatty areas, but don’t remove too much of the fat. It will render and contribute to the flavor of the final dish.
Blend the butter and herbs. Remove the leaves from the rosemary sprigs. Place the rosemary leaves, sage and butter in a blender or food processor, and process until fully blended. Season the mixture to taste with plenty of salt and pepper.
If you like thyme, add the leaves from two sprigs of thyme as well.
Add extra rosemary or sage according to taste.
Make pockets in the lamb shanks. Use a sharp knife to slightly separate the meat from the bone at the base of each lamb shank. Put your finger into the holes you’ve created to make a small pocket in each shank.
Don’t completely remove the meat from the bone. Just separate it enough to create a little pocket.
Stuff the pockets with the butter mixture. Divide the mixture between the four shanks, using a spoon to stuff it deep into the pockets. As the shanks bake, the butter will melt and flavor them from the inside out.
Place each lamb shank on a folded piece of aluminum foil. Tear off four large pieces of aluminum foil and fold each one in half. Place one lamb shank in the middle of each piece of foil. They should each be in an upright position, with the bones pointing up. Gather the edges of the aluminum foil around the shank and toward the bone, so that each shank is sitting in a sort of bowl shaped from aluminum foil.
Make sure you use enough foil so that it won’t rip. You need enough to gather the ends over the bone before putting the packets in the oven.
Add vegetables and wine to each packet. Divide the vegetables evenly among the packets. Divide the garlic cloves evenly among the packets, too. Finally, divide the wine evenly among the packets, pouring a few glugs into each.
Close the packets. Twist the aluminum foil around the bones so that each packet is tightly sealed. Arrange them on a baking sheet so they won’t drip as they bake.
Bake the packets. Place the baking sheet in the oven and bake the packets for 2 1/2 hours. Check the meat to make sure the lamb shanks are soft and fall-apart tender; if not, return to the oven for a few more minutes.