I’ve been on a mission to find the best french onion soup in New England. For about the past year, every restaurant I go to, if there’s a French onion soup on the menu, I’m ordering it.
There’s actually a good reason behind this adventure. It’s not only because I love the delicious caramelized onions, beefy broth and melted gruyere cheese. I want to know if the French Kiss Sub at Mortadella Head is the best it can be! I want to make Julia Child proud!
In this business it’s important to try other people’s recipes in order to get better. I always learn something new when I eat someone else’s food.
The sub I’m talking about is a big, fat, beautiful steak and cheese plus all of the good things you’d find in a traditional French onion soup. In addition, I smear some delicious horseradish mayo onto the sub roll for some extra depth of flavor.
The ingredients work and people love it!
What is French Onion Soup?
French onion soup, also known as “soupe à l’oignon gratinée” in French, is a delicious soup made with sweet caramelized onions, beef broth and topped with crusty bread slices and cheese.
The interesting thing about this soup is that some people say it’s been around since ancient Roman times! So I guess it makes sense for us to use it at Mortadella Head.
Now that we know it’s actually an Italian soup, let’s move on.
It’s a restaurant favorite here in the United States. This hearty soup can be served as an appetizer or a main dish.
It seems like most restaurants have their own version of the classic French onion soup. The good news is that they’re all usually pretty good.
The Main Ingredients to Make the French Onion Soup Cheese Steak
It only takes some simple ingredients and a little time and effort to make this beautiful steak sandwich.
Onions: the star of the show in this easy French onion soup recipe is obviously the onions. You have a choice of onion in this recipe. You can use yellow onions or white onions.
Butter: you should use unsalted butter for this recipe so you can control the flavor by adding your own salt.
Garlic: get a few fresh garlic cloves. Try to find garlic grown in California.
Beef Stock: you can buy beef broth or a good beef stock at the grocery store. You can also take the time to make it yourself. If you make it yourself it will add on some extra work, but the rich flavor will be worth it.
Wine: you can use a white wine such as a Sauvignon Blanc or Pinot Gris. I also like to add a little Sherry for some sweetness.
Steak: I suggest getting some shaved ribeye for this twist on the cheese steak. Ribeye is good because it has just enough marbled fat to give it lots of flavor.
Cheese: a couple cheeses are needed for this beautiful sandwich. Get some grated parmesan and Gruyere cheese. If you can’t find Gruyere, you can use Swiss.
Bread: for this sandwich you should use a crusty bread that is strong enough to hold all of the ingredients. A loaf of French bread that’s soft in the middle and crunchy on the outside is what I like to use.
How to Make a French Onion Soup Cheese Steak
At the restaurant we make this on a flat top grill, but it’s just as easy to make in a frying pan at home.
The first step is to preheat the oven to 375° F.
Now melt the butter in a large pot or Dutch oven over medium heat and add your thinly sliced onions and garlic.
Season the onions and garlic with salt and pepper and let them caramelize nice and slow for about 30 minutes. For the best results you want the onions to have a deep brown color. When they are dark brown you know they are ready.
Add the Sherry to the onions and deglaze the bottom of the pan. Use a wooden spoon to loosen up any of the browned bits. Let them cook for another 10 minutes.
Add the white wine to the pot and let the wine reduce for an additional 10 minutes.
Now add your meat stock and bring it to a boil. Once it starts to boil, turn the heat down to low heat and let it simmer for 45 minutes.
Take a frying pan and add a little olive oil. Heat the olive oil on medium high heat.
Add the shaved steak to the pan and break into little pieces with a wooden spoon.
Open your sub roll with a knife and spread on some butter. Add grated parmesan cheese and put it in the oven until golden brown. When you remove it from the oven, rub a fresh garlic clove all over the inside of the toasted roll. We’re making garlic bread similar to the cheesy toast you get on top of the soup.
Using a slotted spoon, take a heaping spoonful of onions out of the soup pot and place them on top of the steak. Mix the onions and steak well until the onions are completely incorporated.
Cover the steak and onions with lots of gruyere cheese and let it melt.
Slather some horseradish mayonnaise inside the roll.
After the cheese melts, fill the toasted sub roll with the steak, onions and cheese. Serve a cup of the soup on the side for dipping.
French Onion Soup Cheese Steak FAQs
Q: What other kind of broth can be used for a French Onion Soup?
A: Traditionally a beef stock is used, but you could use a chicken stock or vegetable stock. Don’t expect the same rich flavor that you get with beef stock.
Q: Are there other sandwiches I can make with the French Onion Soup?
A: Yes. If a cheese steak isn’t your thing you can make some other awesome hot sandwiches. Make a chicken sandwich with grilled chicken breast. You can also make it with roast beef and do a French dip.
Instead of shaved steak you can use ground beef and make a French Onion Chopped Cheese sandwich.
Q: I don’t like Swiss cheese so what else can I use?
If you don’t want to use Gruyere or Swiss cheese, try using a low moisture mozzarella cheese or provolone. They both melt really nice and have lots of flavor.