Finely chop two leeks and saute until translucent. Add 1 TB. of flour, sook and stir for a couple of minutes. Add 2-3 potatoes, cut into large chunks, and enough water (or vegetable broth) to cover. Salt and pepper to taste. Simmer for about 30-45 minutes, until the potatoes are tender. Remove from heat and break up the potatoes with a masher, so that you have a chunky soup, or you can puree until smooth. Add a large spoonful of sour cream or yogurt, stir in, and serve.

{Via Kathy}