Begin by melting the butter with the olive oil in a large heavy based pan. Add the onions, garlic and 3 sprigs of thyme. Fry with the lid on for 10 mins until they’re fairly soft. Remove the lid and turn the heat up a little and continue to cook for 35 minutes, you may need to reduce the heat towards the end of the cooking time as the onions begin to catch and caramelise. Add the sherry vinegar and black treacle then stir and cook for a minute or 2. Now add the cider and stock, season with salt and pepper, cover and cook for 10 minutes.

Rinse the pearl parley, place in a pan of boiling water, simmer for 10 minutes, drain then pour into the soup. Continue to simmer the soup for a further 10 minutes or until the barley is cooked. Check the seasoning, add more salt & pepper if necessary.

Cut the shallots in half lengthways, no need to peel. Heat a frying pan with a drizzle of olive oil and place the shallots cut side down in the pan. Cook until they blacken. Remove from the pan and separate the layers and have them ready to garnish the soup.

Lightly toast the sourdough slices then top with the cheese and place under a hot grill. Cook until the cheese is bubbling. Cut into slices and serve with the soup and garnish with the shallots and fresh thyme.