Turn the oven on at 175°C. Heat an oven proof skillet on medium. Add a generous glugg of olive oil.
Sear the leeks on both sides until golden brown. Nestle in the garlic (save one teaspoon), drained beans, and scatter over the chili flakes. Season with salt and pour over the broth and vinegar. You want the leeks to be covered halfway with broth.
Roast for 20-30 minutes, until the leeks are soft and most of the liquid has evaporated.
Stir together the greek yogurt and the reserved minced garlic. Season with salt.
Spoon the greek yogurt on a plate. Top with leeks and beans, spooning over remaining sauce.
Finish with fresh herbs of your choice and serve with crusty sourdough bread.
