Cut the ends off the leeks, quarter them lengthways, wash them under running water and cut them into thin slices.
Heat 2 Tbsp oil in a large pan on a high heat, add all the chopped and sliced ingredients and cook with for 10 minutes, or until softened, stirring regularly.
Add potatoes and stock. Bring to a boil, then reduce the heat to low and simmer for 10 minutes with the lid on. Remove from heat.
Season to taste with salt and pepper, then either serve as is or blend for a smoother texture.
