This classic French Onion Soup includes flavorful broth topped with toasted sourdough croutons and plenty of melted cheese! It’s the perfect fare for cold winter evenings!
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The key to making a good French Onion Soup is time. It’s not a difficult recipe by any means, but the base of French Onion Soup is caramelized onions. And to caramelize onions, you need time. The first step is slicing up all of the onions, and let me warn you now: you’ll likely be balling like a baby after slicing up 6 large onions. (If you can only find medium onions in your store, then you’ll need to slice even more onions!) I put all of those sliced onions into a 5½-quart Dutch oven…and they barely fit. As in, I had to press the onions down lightly just to get the lid on. As they cook, the onions reduce in volume quite a bit. By the end, they only covered the bottom inch or two of the pan.
Have y’all ever made caramelized onions? They have such a unique flavor, and they’re really not hard to make at all. Caramelized onions are actually one of my favorite toppings for toasted sandwiches. Have you ever made a grilled cheese sandwich with some caramelized onions in there? (Hint: Do it.)
So what is caramelizing? It’s the process by which the sugars in the onions cook. Caramelization happens over a long period of time at a low temperature, and the result is a pile of dark brown onions with a distinctively sweet flavor. But caramelization takes time. For 2-3 onions, it’ll take about 45 minutes. For 6 onions, it took me about 80 minutes. But that’s simply because I had so many onions that they steamed first and released a bunch of water…then that water had to evaporate before the browning could begin. But it’s all good. Laura and I were just watching a movie, and I hopped up and stirred the onions every 15 minutes or so.
Aside from caramelizing the onions until they are deep brown in color, the other key to a good French Onion Soup is the topping. I used a combination of Swiss and Gruyere cheeses. Both types of cheese melt well, and Gruyere has a noticeably nutty flavor. This nuttiness combined with the sweet caramelized onions is a match made in heaven. Seriously! Oh, sourdough. I almost forgot to mention that I always use sourdough when making French Onion Soup. The slightly sour taste just helps balance out the sweet caramelized onions.
Funny side story: I made 2 crocks of this French Onion Soup for these photos. But there’s only 1 crock in the photos. That’s because I happened to like the look of this crock better…and I also happened to eat all of the cheesy sourdough croutons (with the bottoms soaked in broth, mind you) while I was taking these photos. Hey, the chef always has to taste his or her creations, right?
I hope the new year is off to a great start for you so far! And might I recommend a nice hot bowl of this French Onion Soup this weekend? It’ll warm you right up…I promise!
French Onion Soup
For the Caramelized Onions
For the Caramelized Onions
- Using a large stockpot or Dutch oven, add butter and olive oil. Place over medium heat until butter melts.
- Add onions; cover and cook, stirring occasionally, for 15 minutes, or until onions have softened.
- Add sugar, salt and pepper. Continue cooking uncovered, stirring occasionally, for 60-65 more minutes, or until onions have turned dark brown in color. (Note: If the onions begin to scorch or stick to the bottom of the pan, turn the heat down. The secret to caramelized onions is low and slow!)
For the French Onion Soup
- Once the onions have caramelized, add flour and thyme; stir until well coated. Continue cooking 1-2 minutes, stirring constantly.
- Add white wine, brandy (optional), mashed roasted garlic and broth. Bring to a boil and then reduce heat to low; simmer for 45 minutes.
- Meanwhile, toast the bread cubes until crispy and lightly browned.
- Using a medium bowl, combine the grated gruyere and Swiss cheeses.
- Ladle soup into broiler-safe crocks. Top with several toasted bread cubes and ¼ cup of grated cheese.
- Place crocks on a baking sheet and broil until cheese has melted and begun to turn brown.
- Serve hot.