French onion soup final

Comfort in a bowl 🔥 restaurant-level French onion soup… at home.

Serves: 4
Total time: ~1.5–2 hours (mostly hands-off)

Ingredients

1.25–1.5 kg yellow or large sweet onions (about 8 large onions, 10–12 cups thinly sliced)

3 tbsp salted butter (42 g)

1 tbsp olive oil (15 ml)

1 tsp kosher salt to start, plus more to finish

1 tsp granulated sugar (5 ml)

1 tbsp flour (8 g)

½ cup sherry cooking wine (125 ml)

1.5–1.75 L beef stock (6–7 cups)*

2 sprigs fresh thyme

1 bay leaf

¼ tsp Worcestershire sauce

½ tsp balsamic vinegar

A few drops of soy sauce

Baguette, sliced 1.5–2 cm (½–¾ inch) thick

200 g Gruyère (7 oz), grated — about 1½–2 cups loosely packed

30 g Parmesan (1 oz / about ¼ cup), finely grated

Freshly ground black pepper

Fresh chives, finely chopped

A note on stock

The best option is high-quality homemade or butcher-made beef stock.

For my version, I used a combo of 1 L butcher beef stock from the butcher, plus 500–750 ml regular chicken stock (I use better than bouillon), which worked beautifully. The range accounts for how much the soup reduces while cooking — add more as needed before finishing.

If good beef stock isn’t available, consider using entirely chicken stock — homemade ideally, but regular store-bought chicken stock is often better than beef.

Instructions
1. Melt the butter and olive oil in a large Dutch oven over medium heat. Add the onions and toss to coat. Sprinkle with 1 tsp salt and cook for about 10 minutes until softened, stirring every 1–2 minutes.

Reduce the heat to medium-low and cook for 45–60 minutes, stirring occasionally, until deeply golden. Once the onions turn a deep golden brown colour, stir in the sugar to encourage browning. Do not rush this step! Colour means flavour.

2. Sprinkle the flour over the onions and cook for 1–2 minutes, stirring well.

3. Add the sherry, scraping up any browned bits from the bottom of the pot. Simmer for 2–3 minutes until the alcohol aroma cooks off and the liquid mostly reduces.

4. Add the stock, thyme, and bay leaf. Bring to a gentle simmer and cook uncovered for at least 30 minutes, until slightly thickened with a glossy consistency. If over-reduced, add more stock as needed to loosen. Remove the thyme sprigs and bay leaf.

5. Stir in a few drops of Worcestershire sauce and simmer for 5 minutes. Turn off the heat, add the balsamic vinegar, and taste. Depending on your stock, the salt level may already be sufficient. If needed, add soy sauce drop by drop just for a slightly more savoury depth.

Finish with black pepper and adjust salt only if needed. Adjust the vinegar, soy, and Worcestershire cautiously and note that small amounts make a big difference.

6. Preheat the oven to 400°F. Toast the baguette slices until lightly golden, then switch the oven to broil. Ladle the soup into oven-safe bowls, top with bread, and cover generously with Gruyère and Parmesan. The cheese should cover the bread and surface of the soup without being piled too high.

Broil until melted, bubbling, and lightly golden. Top with chives and serve immediately.

Notes

Start lighter on salt than you think. It’s tempting to season aggressively from the start, but when reducing a dish for this long, the flavours concentrate quickly. Start light, and taste towards the end before final seasoning.

Stir less than your instinct tells you. Contact with the pot builds flavour, but it takes time. Keep the onions on medium-low, despite the temptation.

Acid goes in last. It brightens the entire soup.

Great onion soup is about onions first, broth second. Spend the time needed to get the onions right.