Bone Broth

Stolen from Smitten Kitchen's Ultimate Chicken Soup recipe, modified to be bone broth, and also for onion diversity.

Ingredients:

• 1 medium-large yellow onions, unpeeled, halved
• 1 large leek, cleaned and cut lengthwise
• 1 shallot, unpeeled, halved
• "2" garlic cloves, peeled and smashed a little
• 1 large carrot
• 1 large parnsip 
• 1 celery rib
• 4 pounds of fresh chicken wings
• 1 tablespoon kosher salt
• 1/2 teaspoon dried thyme or 2 teaspoons chopped fresh
• 1/8 teaspoon red pepper flakes
• 1 tablespoon tomato paste
• 2 bay leaves
• As much water as you can fit in your crock pot basically 

Combine all ingredients in a large (6 quart or larger) slow-cooker. Cook on LOW for 24 hours. Strain. Do NOT attempt to use the chicken for anything; it's super gross. Trust Past Sonja.