1. Heat a frying pan until hot then fry the bacon for 4-5 minutes, or until crisp and golden-brown. Remove the bacon from the pan and set aside. Keep warm.

2. Heat the vegetable oil in the same frying pan and fry the onion and celery for 4-5 minutes, or until softened. Add the potato, leeks, thyme and bay leaf and stir until well combined. Cook for a further 1-2 minutes, then add the stock. Bring the mixture to the boil, then simmer for 10-15 minutes, or until the potatoes are tender.

3. Just before serving, stir in the cream and smoked salmon and season, to taste, with salt and freshly ground black pepper. Ladle the soup into bowls and garnish with the crispy bacon, tomatoes and parsley.