Preheat oven to 400 degrees F. In a large saucepan combine broth and the water. Bring to boiling. Add green beans, parsnips, and shallots. Return to boiling; reduce heat. Simmer, covered, for 8 to 10 minutes or just until vegetables are tender. Remove from heat. Stir in sausage and lentils. In a small bowl combine wine, mustard, thyme, and half of the minced garlic; stir into sausage mixture.
Transfer sausage mixture to a 2-quart casserole. Bake, covered, for 25 to 30 minutes or just until lentils are tender.
Meanwhile, in a medium bowl toss together bread crumbs and oil. Sprinkle over sausage mixture. Bake, uncovered, about 10 minutes more or until mixture is heated through and crumbs are lightly browned.
In a small bowl combine snipped parsley, lemon peel, and the remaining garlic. Sprinkle over casserole before serving. If desired, garnish with lemon slices and/or parsley sprigs.