2 stalks celery medium chop
1 medium onion medium chop
2 cloves garlic
3 1/2 lbs beef or chicken bones or a combination of both
Kosher salt to taste
2 Tbsp apple cider vinegar
Place the bones in your slow cooker, filling about 3/4 of the slow cooker.
Chop vegetables and garlic (no need to peel). Add additional rinsed vegetable scraps and eggshells if desired. You'll be straining these out before storing the broth.
Fill the slow cooker with water and season with about 1 tsp of salt (or to taste).
Add apple cider vinegar (no worries -- you won't notice the taste in the finished product).
Cook on low for 18-24 hours.
Strain everything through a fine-mesh strainer and discard bones and vegetables.
Cool the stock and store in an airtight container in the refrigerator for up to 4 days or in the freezer for 6 months.
Notes Chef Tip: A good broth will usually have a layer of fat on top and will gel when thoroughly cool. Remove the fat with a spoon and discard.