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2.90 from 10 votes

Burnout (Recipe: Slow-cooker Caramelized Sweet Onions)


  • Slow-cooker Caramelized Sweet Onions
  • yield: 1 1/2 pints
  • Caramelizing onions in the slow-cooker is about the easiest thing you will ever do in your whole entire life. You can make a whole batch at once freeze them in small containers and bring out what you will use within a week.
  • The length of cook time will squarely depend on the type and size slow-cooker you use. I set mine on low and let the onions cook for 24 hours. They were perfectly caramelized without being cooked to a mush. The variety of onions will affect cook times also, as each has a slightly different water content. I can't give you the percentage of water contained in each variety of onion nor the anticipated cook times for each make and model of slow-cooker. Rather, I would simply suggest that you make some mental notes the first time you cook these onions to get an idea of the ideal cook time for your situation. If there is a first time for you, a second time will certainly follow. These onions are too delicious, too versatile and too easy to be forgotten.
  • My preference for onions is always sweet onions. I use Vidalias when I can get them. When they're not available I will opt for which ever sweet onions I can get my hands on.
  • 3 pounds sweet onions peeled and thinly sliced
  • 1 tablespoon olive oil
  • 1 tablespoon butter
  • 1/2 teaspoon salt
  • few sprigs of thyme


  • Spray bowl of slow-cooker with nonstick spray to make clean up easier.
  • Add sliced onions and remaining ingredients. There's no need to strip the leaves from thyme. Simply place the sprigs on top and remove them before eating the onions.
  • Cover. Cook on medium/low for 24 hours or on high for approximately 8 to 10 hours until the onions are a deep caramel color. Stir once or twice toward the end of the cooking time.
  • Use on sandwiches, salads, omelettes, soups. Serve as a side dish with meat. Chop fine and mix with butter for a delicious compound butter that is outstanding atop steaks. Use a garnish for dried beans (navy, pinto, blackeye peas, etc.). I'm making French Onion Soup with these babies!
  • Freeze in small containers. Take out only what you think you will use up in a few days.
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