(Note this has a 7 hour total cooking time)Peel and slice onions, about ¼ inch thick.
Place onions in a slow cooker.
Place the cut butter on top of the onions.
Sprinkle salt and sugar.
Cover and cook on High for 5 hours.
At this point, you will have a lot of liquid in the onions. Stir and set the lid ajar. Cook for 2 more hours on high.
Serve and Enjoy!
Notes
Can I make a bigger batch?If you'd like to make more, simply double or triple the recipe. You will have to add an additional few hours.Can I freeze the leftovers?Absolutely. They actually freeze quite well and defrost to taste as though they were just cooked. We recommend freezing them in small portions according to how you think they'll be used. Be sure to use freezer bags or containers to maintain freshness. The onions will last three months in the freezer.Can I use a different type of onion?Red onions (also known as purple onions) would be the choice in line for caramelizing as they can also be on the sweeter side than other options. You won't necessarily have that walnut color but more of a grayish color. Overall, you'll want to stick with the sweet onions.Can I use more butter? You can, though your onions will have a lighter color for they won't be able to brown as much in the extra liquid. But will be very buttery and delicious.