Slow Cooker Caramelized Onions

While stovetop caramelization requires constant attention and can take up valuable time, this slow cooker method allows you to achieve that perfect deep color without the hassle.

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Ingredients

5 lbs Yellow Onions You can also use a blend of onions. Each of my onions was a full pound on it's own so I ended up using 5 onions.
2 tbsp Salted Butter
2 tbsp Olive Oil extra virgin
1/2 tsp Sea Salt
1 tbsp Balsamic Vinegar optional

Instructions

Peel and thinly slice the onions. The slow cooker allows you to be lazy—no need to worry about precision here. I like to start by cutting each onion in half down the middle, and then making thin slices from each half.
Place the sliced onions in the slow cooker, drizzle with olive oil and place the butter on top. Sprinkle with a pinch of salt. If you like, add a touch of sugar to enhance the caramelization process. I do not use sugar in my recipe, but some people like it.
Cover the slow cooker, set it to low heat, and let the magic happen. Stir occasionally if you can, but it's not necessary. The onions will gradually transform over the next 12 -16 hours, intensifying in color and flavor.
If you are slow cooking a large amount of onions, a lot of water will come out of the onions. I like to cook them on low for about 10-12 hours, and then I put the heat on high and slow cook on high for the remaining time with the lid slightly ajar.

Notes

Slow cooking onions will give you brown onions with a luxuriousness richness, but they will not give you the same crispy edges that the traditional stove-top recipe will give you. If you would like crisp edges, I suggest slow cooking in a large batch and then, when you are ready to use your onions, add them to a pan for about 10 minutes and you will have the results you want.