In 15x10x1-inch pan, place carrots, celery, parsnips, potatoes, onion and garlic.
Drizzle with oil; toss until well coated.
Roast uncovered 30 minutes, stirring once halfway through cooking time.
(Vegetables will be browned, but may not be tender or fully cooked. )
In 6-quart slow cooker, place roasted vegetables and remaining ingredients.
Cover; cook on Low heat setting 7 to 9 hours or on High heat setting 2 hours 30 minutes to 3 hours 30 minutes hours.
Pour stock through fine mesh colander to strain out vegetables and herbs; discard vegetables and herbs.
Notes / Tips / Wine Advice:
Use stock in 3 to 4 days, or for longer storage, pack stock in freezer containers, label and freeze. Be sure to pack the stock in containers with about the amount of stock you anticipate using in a recipe, for example, 2 cups. Freeze for up to 3 months. To use, thaw the stock overnight in the refrigerator.