Preheat oven to 375 degrees. In deep skillet, coat leeks and carrots with olive oil. Cover and simmer over low heat until soft. Add seasonings. Mix well. Layer a well-oiled 2.5-to 3-quaart casserole (with cover) with one third of the potatoes, then half the seasoned vegetables. repeat and finish with last one third of potatoes. Pour broth evenly into casserole. Cover and bake for 50 minutes covered at 375 degrees. Uncover and bake for another 20 minutes. Garnish with parsley and chives. Variation: Substitute carrots with zucchini if desired. Half of leek can be finely chopped yellow onions. Per serving: 290 calories. 7 grams fat.