- Heat a splash of extra-virgin olive oil in a large saucepan over medium heat. Add the leeks and season generously with sea-salt and freshly-ground black pepper. Cook, stirring occasionally, until softened, 5 to 7 minutes.
- Add the garlic and cook, stirring constantly, for 1 minute then add the frozen peas and stock. Season generously with sea salt and freshly-ground black pepper and stir to combine. Cover, turn the heat up to high and bring the soup to a boil. Once boiling, reduce the heat to medium and simmer, covered, for 3 minutes.
- Remove the saucepan from the heat. Stir in the mascarpone and fresh mint. Purée the soup in a blender until silky smooth then pour it into a clean saucepan. Season with salt, to taste.
- Reheat the soup to a gentle simmer, adding some extra stock if the soup is too thick for your liking. Pour into bowls and serve with crusty bread – enjoy!