3 slices good crusty bread, toasted and torn into chunks
Heat the olive oil in a large saucepan and gently fry the celery, carrots, onion, garlic and thyme for 10-15 mins until softened. Meanwhile, cover the porcini with hot water and soak for 15 mins until softened and swollen. Drain the mushrooms, reserving the soaking liquid, and roughly chop. Add to the softened vegetables along with the soaking liquid and cook for another 5 mins.
Stir in the tomatoes and cook for 10 mins until they begin to break down, then pour in the stock and bring to a gentle simmer.
Poach the 6 eggs in a separate large saucepan of simmering water for 3-4 mins until set, then remove with a slotted spoon. Add the parsley and a little seasoning to the soup, and mix in the torn-up toasted bread. Divide the soup between 6 bowls and place an egg on top of each. Serve scattered with extra thyme.