About this recipe: Make beautifully caramelised onions in your slow cooker with this easy recipe. Ideal for soups, burgers, omlettes, pizzas and more.
Substitute butter with olive oil, if desired.
Instead of straining off the liquid (and onion sugars), just cook with the lid off on high, stirring occasionally. I made these to go with some collards (which needed that extra sweetness from the onion to counter the bitterness of the greens). Worked beautifully! - 09 Oct 2016 (Review from Allrecipes US | Canada)
This was the easiest way to make carmelized onions I've ever tried. The up side was that they were perfect and tasted fantastic. The down side is that it takes 10 - 14 hours to completely carmelize the onions using the slow cooker. If done for 10 hours, there is a lot of liquid to be drained off for use in another dish (French Onion soup maybe?). If cooked for the additional 4 hours with lid slightly off set, the liquid evaporates and the onions become a deeper caramel color. If you don't need them right away, this is the way to go as they can be frozen; otherwise they'll need to be done in the skillet which is definitely quicker but much more labor intensive. - 27 Nov 2016 (Review from Allrecipes US | Canada)
Great and easy to make. I used them in the slow cooker french onion soup recipe on this site. Started the evening before hitting the sack and in the a.m. added the rest for the soup. I would suggest adding a little sugar depending on the type of onions you use. Mine were the ordinary yellow onions - 12 Nov 2016 (Review from Allrecipes US | Canada)