By the time the first shoots of green are coming up, the idea of "fresh vegetables" is getting a little thin. Likely even the last of the winter squash are gone, and the only thing that remains are potatoes and onions. Here's a classic recipe for French Onion Soup which will make the most of the onions that still linger, and warm your soul in the process. Bonus for using yesterday's bread, which is the perfect texture for topping a bowl of soup.
Caramelize the Onions
French Onion soup is more of a process than a recipe, and it starts with the onion.
Caramelized onions are great in so many dishes, including quiche or focaccia, and as a topping to burgers, grilled cheese sandwiches, or on a BLT. Put them on anything and everything. Your friends will think you are gourmet, and your taste buds will love you for it. And really, if couldn't be simpler. It takes some time, but you can absolutely caramelize onions in advance and keep them in the fridge for a few days. They'll keep in the fridge for up to four days, so this makes them an excellent weekend cooking task.
The best onions to use are sweet ones, like Walla Walla or Vidalia, but you can mix it up with sweet and yellow onions. If all you have the the old yellow standby, just add a splash of balsamic vinegar ot a pinch of brown sugar after the onions have caramelized.
Slice the onions thinly and add them with a pinch of salt to the pot on top of the melted butter. Start on medium heat, then lower it. Gentle heat is what allows the caramelization to happen. The whole process will take 45 minutes to an hour depending on your stove and the amount of onions you're cooking. If you're using a skillet, tongs make the turning process easiest. You want to be able to turn them so that they cook evenly. Once they start to soften and turn golden brown, lower the heat. If the onions are sticking at all, add a splash of balsamic vinegar to deglaze the pan. Continue stirring over low heat until the onions are the color you want. If you're using the onions in soup, add a splash of broth at the end to pick up all the browned bits and deepen the flavor.
Broth
Beef stock or broth is the hearty base to this recipe, and what makes it stand out. You can use vegetable or chicken stock, just be aware that it will change the flavor profile a bit. If you are making your broth from scratch, this is the perfect way to use it. You can add some red wine or sherry to the soup pot after you pour in the broth to give it that classic French Onion Soup taste. The alcohol will cook out.
Pour the broth over the onions and bring to a vigorous simmer, covered, for 10-20 minutes, stirring as needed. When the soup darkens and the aroma fills the kitchen, it ready. Slow cooker note: The caramelized onions can be placed in a slow cooker with the broth and heated on low for 8-10 hours or high for 4-6 hours.
To serve, ladle the soup into ramekins, bowls, or mugs, filling halfway to two-thirds. Add a piece of crusty bread on top and cover with thinly sliced cheese. I like Gruyere cheese here. Bake in a 425 degree oven for about 10 minutes, until the cheese is melted and slightly browned. Serve with milk and more bread.
Ingredients
1/4 c. butter, melted*
2-3 onions
Pinch of salt
Balsamic vinegar
4-6 c. broth
Swiss cheese, sliced thinly
*You can use 3-4 Tablespoons oil instead. I like to use a high quality olive oil if I'm going that route. You can also go half and half on butter and oil (or any ratio you like).
