Heat a medium soup pot over medium-high heat. Add a drizzle of olive oil, then add the bacon and cook until crisp. Remove the bacon with a slotted spoon and set aside.

Add the celery, carrots and leeks and cook until tender. While the vegetables are cooking, slice the potatoes. To slice, cut the potatoes into thirds, then thinly slice. Add the bay leaf to the vegetables and season with salt and pepper.

Add the chicken stock and bring to a boil. Add the potatoes and tomatoes then reduce the heat. Cook until the potatoes are tender. Return the bacon to the soup. Add the parsley and salt and pepper to taste. Serve.