Slow-Cooked Leeks, Yoghurt and Walnuts

• 25 g butter
• 1 tablespoon olive oil
• 600–700 g

To cook the leeks, melt the butter with the olive oil in a small-medium pan. When bubbling and golden, add the leeks and half the mint and season with salt and pepper. Cook over a medium heat for about 15–20 minutes, stirring occasionally or until they are soft and sweet.

To make the stabilised yoghurt, place all the ingredients in a bowl and whisk until smooth. When the leeks are ready