Boil 2 cups of water in a small pot. Add the porcini mushrooms in the boiled water to soften. When they become soft, take mushrooms out of the water. Keep the water for the braising later. Roughly chop mushrooms.
Select SEAR/SAUTÉ Mode. Press the Temp/Time button to set the time to 30 minutes with the knob. Press START .
Season short ribs with salt and black pepper. When the cooking vessel is hot, place ribs to the bottom and sear both sides until browned (roughly 5 minutes each side).
Take the ribs out and put onto a plate. Discard the grease remaining in the vessel. Be careful, the vessel will be hot. Use silicone gloves to touch the handles.
Add olive oil to the vessel. Sauté onions and garlic until soft for three minutes.
Stir in the cremini mushrooms and porcini mushrooms. Sauté until the liquid released from the mushrooms have evaporated.
Add the left-over liquid from the soaked mushrooms, thyme and beef stock to the pot and place ribs on top. Make sure the ribs are mostly covered with liquid. Press CANCEL .
Close the lid. Select BRAISE MODE. Press the Temp/Time button and set the time to 2 hours. Press START.
After 45 minutes skim any fat from the surface and stir in the barley. Ensure that the barley is fully submerged in the liquid (to help you can place ribs on top to keep the barley submerged).
Wait for 30 minutes and check the ribs, make sure they are very tender and carefully take them out and place onto a plate. Try to leave all the barley in the vessel.
Add the balsamic vinegar and parmesan to the pot, and mix in with the barley until creamy. Add in additional hot broth if needed. Adjust seasoning to taste.
Mix in parsley and lemon zest. Press CANCEL .
Serve the barley mixture on a plate and place the ribs on top. Garnish with chopped parsley.