Caramelized onions are a delicious, sweet yet savory condiment to have on hand. You can add them to a variety of dishes (like our perfect mashed potatoes) and they can even serves as a spread of their own. Many people confuse “browned onions” with “caramelized” onions so we wanted to show you exactly how to make real caramelized onions with a step-by-step guide.
The first decision you have to make is on the type of onion to use. For this, stick to regular yellow onions or our preferred type – sweet Vidalia onions. They have an extra natural sweetness that caramelizes beautifully. Stay away from the white or red onions for this recipe. They’re great for other dishes but not for this.
The real secret of proper caramelized onions is just one simple thing: time. Unlike sauteing or browning onions, which you can do over higher heat, true caramelized onions need to be cooked low and slow so the moisture can evaporate and the sugars will caramelize evenly. The result is a batch of caramelized onions that are silky smooth, evenly browned without charred spots, and impossibly sweet.
Let’s go through the stages so you can see how it comes together.
To Prep: Slice up all of the onions.
First: Melt the butter over medium heat.
Then: Add all of the onions at once along with the salt and toss to combine. The salt will help release some of the moisture and cause the onions to sweat instead of sauté so they don’t brown too quickly.
After 15 minutes: You’ll notice that the onions have released a lot of liquid. Don’t worry, this is completely normal and what should be happening. This is all of the excess water that the onions have released and that we want to cook off.
After 30 minutes: There’s still a good amount of liquid in the pan but you’ll start to see the first signs of browning.
After 45 minutes: Slightly less water but not too much of a change. This is when you want to start keeping a closer eye on it and stirring more frequently.
After 60 minutes: Most of the water has evaporated and things start moving along a little more quickly. Stir often and add a tablespoon of water if you notice any scorched bit
After 1 hour 15 minutes: The onions will be deeply caramelized and almost silky. You know they’re done not only by the color but also by the fact that they release a little bit of oil. You could keep going and make them even darker if you want, but we like this dark golden color.
That’s it! As long as you take things low and slow, your patience will be rewarded. This process allows all of the moisture in the onions to be drawn out then to evaporate. As this happens, the natural sugars in the onions caramelize from the heat, creating an intense flavor.
Perfect Caramelized Onions
Time: 1 hour 15 minutes
Yield: 1 cup
6 cups sweet yellow onions, sliced (approximately 2 large onions)
3 tablespoons unsalted butter
½ teaspoon kosher salt
¼ teaspoon freshly ground black pepper
In a large, deep saucepan, melt the butter over medium heat until foaming.
Add the onions and salt and stir to coat. Cook over medium-low heat for approximately 1 hour to 1 hour 15 minutes until deep brown. If you notice some browned bits on the bottom along the way, add a tablespoon of water and reduce the heat slightly. You want the onions to caramelize slowly and evenly.
Store in the fridge for up to 5 days or in ice cube trays in the freezer for 3 months.