UBS Virtual Cooking Class: Cozy French Onion Soup, from Scratch

NOTE: This event is for UBS employees only. Be sure to register using your ubs.com email address. One registration per employee please.

This event is optional and not firm-mandated.

French Onion Soup

Serves 4 - 6; Sydney Willcox

Soup

3 lb yellow onions (about 6 large)

4 tbsp unsalted butter

Kosher salt and freshly ground black pepper

1 tbsp all-purpose flour, optional

2 tbsp Cogac

½ cup dry sherry, white wine or vermouth

6 cups low-sodium beef stock (or half beef, half chicken)

3 sprigs fresh thyme

1 - 2 bay leaves

1 - 3 tsp sherry vinegar

Topping

1 baguette, sliced ¾ inch thick (1 to 2 slices per bowl)

1 garlic clove, halved

8 - 10 oz Gruyère, freshly grated

¼ cup Parmesan, freshly grated

1. Slice the onions. Halve them and slice pole to pole (root to stem), about ¼ inch thick.
2. Caramelize the onions. In a wide stainless steel pot or cast iron Dutch oven over medium heat, melt the butter. Add the onions and about 1 tsp salt. Cook, stirring occasionally, until they begin to soften. Lower heat to medium low and cook until fully translucent and collapsed. Continue cooking until the onions are deeply golden brown, very soft, and jammy, 45–75 minutes. As the onions become very soft and golden, stir more frequently. Adjust the heat between medium and medium-low: You want enough heat for browning but not so much that the sugars sitting on the bottom burn before the rest of the onions catch up. When brown fond accumulates on the bottom, deglaze with 1–2 tbsp water. Scrape up the browned bits and incorporate them into the onions. Continue cooking until the liquid evaporates. Repeat the process (brown → deglaze → evaporate) as necessary until they’re deeply golden brown. Make ahead: caramelize a big batch and refrigerate up to 4 days or freeze in portions.
3. Add flour. For a slightly thicker texture, use the flour; Sprinkle in the flour and cook, stirring constantly, for 1 to 2 minutes or until raw taste is gone.
4. Deglaze. Add the Cognac and cook for about 2 minutes, scraping up any browned bits. Add the sherry or wine and simmer for about 4 minutes, until reduced by roughly half.
5. Simmer. Add the stock, thyme, and bay leaves. Bring to a simmer, then reduce to a low, gentle simmer for 30 minutes.
6. Prep the bread. Heat the oven to 375°F. Bake the baguette slices on a sheet pan for 8 - 14 minutes, until fully crisp and lightly golden. Rub one side of each slice with the cut garlic clove.
7. Finish the soup. Remove the thyme stems, bay leaves, and any rind. Stir in 1 tsp of vinegar. Season with pepper and salt, and add more vinegar, ½ tsp at a time, until bright and balanced.
8. Assemble. Heat the broiler with a rack about 6 inches from the element. Set oven-safe crocks on a sheet pan and ladle in the soup, leaving about an inch of space at the top. Float 1 to 2 bread slices on each. Pile on the cheese, letting it drape over the rim.
9. Broil. Broil on the top rack for 3 to 5 minutes, watching closely, until bubbling and browned in spots. Rest 5 minutes before serving, since the bowls will be extremely hot. No crocks? Broil the bread and cheese on a sheet pan, then float them on top of the soup.

To Upgrade the Stock *Use 1 - 2 ingredients

• 1 Parmesan rind
• 2 - 4 garlic cloves, smashed
• A few dried porcini mushrooms
• 1 tbsp soy sauce or Worcestershire
• ¼ tsp fish sauce
• 1 tbsp tomato paste

1. Very gently cook the stock at the lowest heat setting for 10 - 20 minutes with 1 - 2 of the upgrade ingredients. Strain if you used porcini.

Fall Variations

Sage

1. Cook the onions in brown butter with 3 to 4 whole sage leaves (remove them at the end of step 4).
2. Garnish with sage leaves fried crisp in butter, or drizzle with brown butter and sage.

Roasted pumpkin or squash

1. Roast ½-inch cubes of pumpkin, butternut, or kabocha at 425°F for 25 to 30 minutes, until browned.
2. Blend about 1 cup into the soup at step 8 for body and sweetness, or float the cubes on top for texture.
3. Keep the onions the star. Too much squash and it becomes squash soup with cheese.

Apple cider

1. Reduce 1 cup cider by half and use it in place of some of the wine in step 6.
2. Finish with cider vinegar instead of sherry vinegar, and use Calvados instead of cognac.

Other swaps

• Cheese: aged white cheddar, fontina, smoked Gouda, or Taleggio with the Gruyère.
• Beer: a brown ale or stout in place of wine for a maltier soup.
• Spices: a pinch of nutmeg, or a little rosemary alongside the thyme.
• Toppings: pepitas, crispy shallots, pear slices, crispy prosciutto or bacon, or sautéed mushrooms.
• Vegetarian: use mushroom stock with 1 tbsp white miso and a few dried porcini, and skip the soy, fish sauce, and Parmesan rind.