Heat olive oil in a large saucepan over medium heat then add bacon. Fry and cook for 2-3 minutes until crisp. Dish out and set aside.
Add garlic and leek to the remaining oil in the saucepan. Fry for 2-3 minutes until fragrant. Add cauliflower and potato then pour in stock. Cover the saucepan partially and allow to boil. Reduce the heat and simmer, stirring occasionally for 20-25 minutes or until all vegetables are tender.
Add half portion of prefried bacon to the soup. Stir to mix. Adjust seasoning to taste.
Tip the contents of the soup into a food processor. Blend until smooth. Return to the saucepan and cook over low heat. Stir in cream and heat up, without boiling, until soup is hot.
Ladle into soup bowls and garnish with some of the remaining fried bacon and a dash of freshly ground black pepper.