Slow Cooker Caramelized Onions

Caramelized onions in crockpot

5 from 1 reviews

Slow Cooker Caramelized Onions let you make a big batch without having to spend an hour at the stove. Just add your sliced onions to the crockpot with some butter and let your crockpot do the work.


  • 4-5 lbs large sweet yellow onions, dependent on slow cooker size
  • 1/4 cup salted butter, melted
  • 1/2 teaspoon kosher salt


  1. Thinly Slice Onions: Peel the onions and cut in half. Thinly slice the onions into thin half moons. I highly recommend using a mandoline but you can also use a very sharp knife. The thinner you slice the onions, the quicker they'll cook
  2. Add to Slow Cooker: Add the thinly sliced onions, melted butter, and salt to the crockpot. It's okay if it's pretty full as the onions will greatly reduce as they cook.
  3. Cook: Cook on low for 10-12 hours, depending on your preference. I like to give them a stir every 2-3 hours for even cooking, but if you're making them overnight then you can skip the stirring step. At 10 hours, they will be lightly browned but have a slight bite. Or you can cook longer for 12+ to get deeper brown onions that are much softer and jammier. If you're going for jammy onions then I recommend leaving the lid slightly ajar for the last couple hours so that some of the liquid can evaporate.


Caramelized onions can be stored in the fridge in an airtight container for 5 days of frozen for up to 3 months.

Keywords: Slow Cooker Caramelized Onions, Crock Pot Caramelized Onions, How To Caramelize Onions

%d bloggers like this: