You can find hind pork shanks in larger supermarkets, where vacuum-sealed and fresh cuts are offered with the bones and skin.
Wash the shank well and spike it with the garlic cloves without tearing the skin. Use the tip of the knife to pierce it and place a peeled garlic clove there.
Sprinkle the shank on all sides with the salt and paprika, then roll in the olive oil. Close it in a bowl with a lid and leave in the fridge for 4-5 hours. At the bottom of an earthenware clay pot, place slices of onions, crosscut into 1/4 pieces.
Cover with the lid and put the clay pot in a lower part of the oven. Turn it on to 356°F (180 °C) and leave to bake for 2 hours. I baked with the fan on. Open it and around the shank lay on the washed shiitake mushrooms , salted beforehand with a pinch of salt.
Put the lid back on and leave to bake another 40 min. Remove the lid and optionally let the meat crisp on top for another 5 min.
For the last part, you can turn the setting to grill with fan on. Chop the parsley before serving, sprinkle the mushrooms with a few drops of the remaining oily sauce.