Add the oil to your frying pan on a low to medium heat, then add in the chopped onions. Fry for 8-10 minutes until soft.
Next, add the garlic and fry for a minute, then add in the wine and the pearl barley. Stir to combine thoroughly.
Add 2 ladle fulls of stock at a time until all the liquid is absorbed.
Fry the mushrooms in the oil in a separate pan, then add in the salt and pepper. Set aside.
When the barley is the consistency, you like it. Add in half the mushrooms, lemon juice, lemon zest, nutritional yeast, salt and pepper and stir well.
For super soft and gooey, add extra virgin olive oil and cover the pan and allow to sit in the pan with the heat off for a further 5 minutes.
Top with the caramelised onions, the remaining mushrooms, toasted hazelnuts and rocket.
Drizzle a good glug of truffle oil over the top.