Make Ahead Tip: Cover and refrigerate for up to 3 days.
Clean leeks well to be sure they're grit-free: After slicing, place in a bowl of water and swish around to release any sand or soil trapped between the layers. Scoop the leeks out of the bowl with a slotted spoon, leaving any dirt behind. Drain well. Repeat as needed.
Slow-Cooker Chicken Stock: Cut 1 medium carrot, 1 celery stalk and 1 small onion into 1-inch pieces. Combine with 4 pounds skinless chicken leg quarters, 6 sprigs fresh parsley, 2 sprigs fresh thyme, 1 bay leaf, 1 crushed garlic clove and 20 whole peppercorns in a 6-quart slow cooker. Add 9 cups water. Cook on High for 4 hours. Strain and let cool to room temperature before refrigerating airtight for up to 1 week or freezing for up to 3 months.
Makes: about 10 cups.
After straining, this stock has negligible calories, nutrients and sodium.