This is not really a recipe, but a good trick to have up your sleeve. Caramelized onions usually take hours of low and slow stovetop cooking with a lot of babysitting and stirring. OR you could just use your crockpot. I take about 5 large onions, use my food processor to slice them, and dump it all in the slow cooker. (This is also a great way to avoid crying while working with raw onions. The crockpot may look full at first, but it will cook down to about 1/3. You needn't add anything else, but you could add a pat of butter or a drizzle of oil. Cook on low for 10 hours.
I freeze this in 1/2 cup portions and use it for all sorts of things. Topping burgers, steaks, pizza, sandwiches, french onion soup, and dips. You can also use them to get a head start on recipes that need cooked onions, like soups and stews. Leave a comment below about what you'll use them for!