Snacks • Christmas

Classic French Onion Soup

Name: Classic French Onion Soup
Prep time: 20 min
Cook time: 1 min
Total time: 1 min
Yield: 6 servings
Ingredients: 3 lb yellow onions, thinly sliced; 4 Tbsp butter plus 1 Tbsp olive oil; 1 tsp sugar; 1/2 cup dry white wine or sherry; 6 cups rich beef broth; 2 bay leaves plus 4 thyme sprigs; 6 thick slices baguette, toasted; 2 cups shredded Gruyere cheese; Salt and black pepper to taste

Deeply caramelized onions in rich beef broth under a blanket of melted Gruyere.

Updated: Nov 9, 2026

⏱ 1 hr 30 mintotal

6servings

320 kcalper serving

Easylevel

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Why you'll like it

Ready in about 1 hr 30 min.
Serves 6 — easy to halve or double.
Easy level — everyday equipment only.
No-cook / minimal cooking.
Storage, freezing and reheating covered below.

This Classic French Onion Soup recipe takes 1 hour 30 minutes and serves 6 as a starter. Slowly caramelized onions in savory beef broth with a toasted bread cap and melted Gruyere make the coziest possible first course for Christmas dinner.

Helpful guides

Instructions

Step 1

Melt butter with oil in a heavy pot over medium heat, add onions and 1 teaspoon salt, and cook 10 minutes until softened and releasing liquid. Salt early to draw moisture.

Step 2

Reduce to medium-low with sugar and cook 35 to 45 minutes, stirring every few minutes, until deep golden brown and jammy. Do not rush; color equals flavor and pale onions make thin soup.

Step 3

Pour in wine and scrape up every browned bit, simmering 3 minutes until the sharp alcohol smell cooks off.

Step 4

Add broth, bay, and thyme and simmer 25 minutes so flavors marry. Season boldly with salt and pepper; bland broth cannot be fixed later.

Step 5

Ladle into oven-safe crocks, float one toast on each, and mound with Gruyere edge to edge so cheese seals to the rim.

Step 6

Broil 3 to 5 minutes until the cheese bubbles and browns in spots. Rest 5 minutes because the soup is molten, then serve on plates to catch drips.

Troubleshooting — fixes, not repeats

If onions burn instead of browning, heat was too high; add a splash of water and lower it.
If soup tastes flat, it needs salt and time; under-seasoned broth is the usual cause.
If cheese slides off, toast was smaller than the crock; use bread that spans wall to wall.
If crocks crack, they were not broiler-safe; check labels before the final blast.

Make it your way

Spicier version: Leftover soup without topping freezes 3 months and reheats beautifully.
Serving with rice or naan: For a slow cooker version, caramelize onions first, then cook everything except bread and cheese on low 6 hours and finish under the broiler.
For a vegetarian version, use rich mushroom broth plus 1 tablespoon soy sauce for depth.
For individual elegance, bake in small cocottes because smaller portions broil faster.

Storage & reheating

Cool leftovers within 2 hours, then refrigerate in a covered container and use within 3 to 4 days. Reheat only the portion you will eat until steaming hot throughout — poultry and reheated rice should reach 165°F (74°C).

Refrigerate soup without topping up to 4 days; reheat to a full simmer.

Freeze the base up to 3 months.

FAQ

Which onions are best?
Yellow onions give the sweetest deep flavor. Sweet onions work but need less sugar. Red onions turn an odd color. Start with the suggested amount, then adjust to suit your taste and equipment.

Can I skip the wine?
Yes, use extra broth plus 1 tablespoon vinegar for brightness. The wine adds depth but the soup stands without it. Start with the suggested amount, then adjust to suit your taste and equipment.

Why Gruyere?
It melts smooth, browns beautifully, and tastes nutty against sweet onions. Swiss works in a pinch; mozzarella turns stringy. Start with the suggested amount, then adjust to suit your taste and equipment.