Slow Cooker Caramelized Onions

Name: Slow Cooker Caramelized Onions
Prep time: 10 min
Cook time: 480 min
Total time: 490 min
Yield: 8 cups
Cuisine: Canadian
Ingredients: 1.5 kg yellow onions (thinly sliced); 2 tbsp olive oil; 1 tsp salt; 1/2 tsp sugar (optional, enhances sweetness)

490 min 8 cups Easy

All Recipes

Transform onions into a sweet, savoury treat with minimal effort using your slow cooker.

Prep

10 min

Cook

480 min

Total

490 min

Servings

Difficulty

Easy

Caramelized onions are a delightful addition to a variety of dishes, offering a depth of flavour that can transform the ordinary into the extraordinary. Traditionally, caramelizing onions involves standing over the stove for an extended period, but our slow cooker version simplifies the process, allowing you to enjoy beautifully caramelized onions with minimal effort. This recipe is perfect for busy cooks who love the rich, sweet, and savoury flavours of caramelized onions but don't have the time to babysit a pan on the stove. Whether you're preparing a gourmet sandwich, topping a burger, or enhancing a soup, these slow cooker caramelized onions will be your new go-to.

Instructions

Prepare the onions

Peel and thinly slice the onions. Aim for uniform slices for even cooking.

Pro tip: Using a mandoline can speed up this process.

Combine ingredients

Place the sliced onions in the slow cooker. Add olive oil, salt, and sugar (if using). Toss to coat the onions evenly.

Pro tip: Ensure the onions are well mixed to promote even caramelization.

Set slow cooker

Cover and set the slow cooker on low heat. Cook for 8 hours.

Pro tip: Stir the onions halfway through to ensure even cooking.

Check onions

After 8 hours, the onions should be golden brown and soft. If not, continue cooking for another hour, checking every 30 minutes.

Pro tip: The onions should have a rich, sweet aroma.

Cool the onions

Once done, transfer the onions to a container to cool. This prevents them from overcooking in the residual heat.

Pro tip: Letting them cool slightly will intensify the flavours.

Store or use

Store in an airtight container in the fridge or use immediately in your favourite dish.

Pro tip: Freeze in portions if you want to store them long-term.

💡

Tips & Tricks

Use a mix of onion varieties for a complex flavour.
Stir halfway through cooking for even caramelization.
Store leftovers in the fridge for up to a week.

Frequently Asked Questions

Can you caramelize onions in a slow cooker?

Yes, slow cookers can caramelize onions over a long cooking time, allowing flavours to develop fully with minimal effort.

How long do slow cooker caramelized onions last?

They last up to a week in the fridge or can be frozen for up to three months.

What are the best onions for caramelizing?

Yellow onions are best due to their balance of sweetness and flavour, but you can mix with white or red onions for variety.

Do you need to add sugar to caramelize onions?

Sugar is optional. It enhances sweetness but isn't necessary; onions naturally sweeten as they caramelize.

Can you speed up the caramelization process?

In a slow cooker, it's best to let them cook slowly for full flavour. Stirring halfway helps even cooking.

Serving Suggestions

These slow cooker caramelized onions can be prepared ahead of time and stored in an airtight container in the fridge for up to a week. They can also be frozen for up to three months, making them a convenient addition to your meal prep routine. Serve them as a topping for burgers, steaks, or sandwiches, or mix them into pasta dishes, soups, and casseroles for added flavour. Pair with a glass of your favourite red wine to elevate your dining experience.