No matter which Mexican restaurant you go to, one of the most popular dishes is probably fajitas. This dish originated as a way to merge Mexican and American cuisine while finding a way to use up cheaper cuts of meat. Through this, fajitas were born and are now known as one of the most popular tex-mex dishes in the United States.
This savory dish usually consists of meat mixed with a variety of vegetables and, of course, onions.
The best onions for fajitas are white onions. These onions provide the fajitas with the most robust flavor and hold up well against the intense heat of the skillet where the fajitas are cooked. Their flavor is also strong enough that it won’t fade into the background behind the chicken or steak.
Even though white onions are considered the best, there are several other types of onions that are used in fajitas and each provides its own unique flavor.
What are Fajitas?
Fajitas are a traditional Mexican-American dish that was developed in the south of the United States. It provides a delicious fusion between the savory flavors of the south and the delicious spices of Mexico.
They were originally developed as a way to use up cheap cuts of meat and make them more flavorful and palatable.
Fajitas are traditionally made using skirt steak sliced into thin strips along with other vegetables including peppers and onions. Then they would be eaten with tortillas, rice, and beans.
Skirt steak is one of the toughest cuts of meat on the cow. In order to make it easy to chew, it needs to be cut into thin strips against the grain of the meat. Cutting it this way helps to break apart the connective tissues making it easier to chew.
If it isn’t cut apart, the steak is extremely tough and cannot be served in one large piece like other cuts of meat.
Why Do We Use White Onions for Fajitas?
Traditionally, the most common type of onion used for fajitas is white onion. White onions are used in fajitas because they typically have a much stronger flavor than yellow or red onions.
They also tend to be crispier when fried up which helps them to hold their own against the chewy texture of the meat. If you use a softer onion, like the red onion or even shallots, you’ll notice that they quickly become soft when exposed to high temperatures. While this is desirable in some recipes, you want to avoid this with fajitas.
If the ingredients used in fajitas are too soft, they can all mesh together into one pile of unpalatable mush. By using vegetables that hold up against the heat better, like bell peppers, broccoli, and onions, the vegetables will maintain their texture. This makes for a dish with a far more satisfying array of textures and individual flavors.
When you cook fajitas, the ingredients are only in the pan for a short amount of time, just long enough to cook the meat. This means that the onion flavor will still be very noticeable since the onions are not being caramelized.
If you used other types of onions, the more mild and sweet flavor will not be as obvious. This can take away from the flavor of the fajitas and make the dish more one-dimensional.
Can You Use Red or Yellow Onions for Fajitas?
While red or yellow onions are not the most common type used in fajitas, this does not mean that you can’t use them if you want to. If you are not a fan of a strong onion flavor or want to add a bit more depth to your dish, substituting yellow or red onions instead of white onions could be the solution.
These onions have a far more mild flavor and can even have a slight sweetness to them. This can help to make the dish more palatable to picky eaters or small children who may not appreciate the bite that white onions give.
What Kind of Onion is Best for Fajitas?
Although white onions are the most common type used in fajitas, there are many variations that call for different types of onions. Some of the onions that you may see in fajita recipes are white onions, Vidalia onions, yellow onions, red onions, and shallots.
1. White Onions
White onions are the most common type of onion used in fajitas. They have a strong onion flavor and very little sweetness. They also hold up well in the pan and need quite a bit of time on the heat before they become soft.
These are also the most traditional option so if you are trying to achieve that classic fajita flavor, go with white onions.
2. Vidalia Onions
Another option that you may see in fajita recipes is the Vidalia onion. This onion looks like a yellow onion but it is flatter in shape and typically smaller.
The benefit of using Vidalia onions is that they are extremely sweet and caramelize rapidly. This can help to add a depth of flavor to your fajitas that is difficult to achieve with other combinations. The sweet flavor can combine very well with vegetables like corn and squash to make a delicious fajita dish.
One thing to keep in mind with these onions is that they tend to burn and should ideally be cooked on low heat. This will allow you to extract the sweet flavor without burning the edges of the onion and making them unpleasant to eat.
3. Yellow Onions
Yellow onions are another relatively common option in fajitas. This is because they are overall very similar to white onions with a bit less bite.
Yellow onions are about the same size as white onions but have a light yellow color instead of white. They also tend to be firmer than white onions.
Overall, they have a very similar, robust flavor that gives a good amount of savoriness to fajitas. The one difference is that they have a bit less bite which is good if you’re feeding children who won’t appreciate the bite that white onions provide.
4. Red Onions
Red onions are probably one of the least used onions in fajitas, but that doesn’t mean that they can’t make for a delicious combination. Red onions are oftentimes smaller than both white and yellow onions and come with a gorgeous purple-red hue. This makes them a popular choice for garnishes where they can add a pop of color.
These are the least spicy of the most common onions and have a slightly sweet flavor. This makes them more popular for sweet recipes or salads where the bite of raw yellow or white onions is undesirable.
5. Shallots
The last option for fajitas is shallots. It is pretty rare to find these used in fajitas, but they can add a flavor that none of the other options can.
These onions are perfectly mild and savory which makes them a great option for people who really don’t like the flavor of onions. They also have a hint of garlic to them which can add an extra level of flavor to your fajitas.
These are more expensive than the other onions on this list, but can still be a great option to enhance the flavor of your fajitas.
Final Thoughts
Fajitas are an extremely popular dish born from a fusion of Mexican and American cultures. Although they are typically based around a cut of meat, usually chicken or steak, there is another very important ingredient that cannot be forgotten, onion.
Onion provides an essential flavor that other vegetables simply can’t provide. White onions are widely considered the best onions for fajitas. They have the most robust flavor and provide an extra spicy bite to the dish.
Other popular onions include Vidalia onions, yellow onions, and, occasionally, red onions.
