If we could sum up the entirety of BBQ with one phrase, it would probably be: slow and low. By utilizing longer cook times and much lower temperatures, we give our proteins time to break down and tenderize to perfection. It’s not always easy, and it’s almost never quick, but the results are absolutely worth the effort.
So, what if we extend this practice beyond proteins? Today, we are going to look at a slow-and-low approach to another common ingredient: onions.
Perfectly caramelized onions are a treat -- sweet as candy, but packing enough complexity in flavor to keep things interesting. Throw a spoonful on top of a perfectly medium-rare ribeye, and you may never go back. A common misconception about caramelizing onions, though, is that you need to rip ‘em to shreds over medium high or high heat. In reality, the barbecue method of slow and low makes some of the best caramelized onions we’ve ever had. And when we say slow, we mean slow. Six hours, in fact!
You definitely can caramelize onions over much higher heat more quickly, but the resulting flavor will be straightforward and relatively uninteresting. By utilizing a slower, lower-temperature method, the sugars in the onions have time to break down and develop a really great depth of flavor, transforming them into something different than what you're probably used to entirely.
It all starts with the perfect onions. We like to do about 6 lbs of yellow, sweet onions at a time. Red onions can be used, but the resulting product will be a little less sweet. Chop your onions up into small-medium sized pieces, and put them in a cast-iron pot with about half a cup of decent quality olive oil. At this point, it will probably look like a lot of onions in there. But don’t worry -- you’re going to see significant shrinkage as the water is cooked out of the raw onions.
Stir the pot a bit to get the onions evenly coated in oil, and then heat your grill or smoker to about 250 degrees fahrenheit. And then, the easiest step yet -- you wait!
Over the next five or six hours, just keep an occasional eye on your pot. It’s a pretty low-maintenance project, truthfully. Perhaps that’s one of the reasons we like this technique so much! You can wander off, spend your time doing other things, while the onions do what they need to do. Although an occasional stir is a good idea, don’t open the pot too much! You want to keep the temperature inside consistent to keep the onions cooking evenly.
Once the onions have reached a dark mahogany color, you’ll know they’re ready. They are probably going to be a lot darker than stove-top or high-heat caramelized onions, but don’t worry -- that’s a good thing.
The color comes from the deep transformation of the sugars in the onions, along with a prolonged exposure to smoke. The only thing left to do is enjoy! We’d suggest throwing some on a steak, or kicking up your next sandwich with a healthy serving of perfectly caramelized onions.