Slow Cooker Caramelized Onions, cooked on high for 5 hours. Just mix yellow onions, butter, sugar and salt in a crockpot and come back to delicious buttery sweet caramelized onions! Freeze in ice cube trays to keep them for months. Save this recipe if you are growing onions in your garden!
Add everything into a large slow cooker and stir so the butter coats the onions completely.
Cook on high for 5-6 hours or until onions become soft and caramelized. My slow cooker usually takes 5 hours.
Serve with your favorite dish, store in the refrigerator for a few days or freeze to preserve. To freeze, allow to cool and then place in ice cube trays and freeze. When frozen, pop them out of tray and place in freezer bags to freeze. Defrost as you need them. Frozen caramelized onions can last 6-8 months.
Notes
This recipe makes approximately 2-3 cups of caramelized onions.