Classic French Onion Soup
Classic French Onion Soup is a medium French recipe that serves 4. 380 calories per serving. Recipe by Martha Stewart on YouTube.
Prep: 20 min | Cook: 1 hr 35 min | Total: 2 hrs 10 min
Cost: $16.59 total, $4.15 per serving
Ingredients
- 2 pounds Yellow Onions (peeled and thinly sliced)
- 4 tablespoons Unsalted Butter (cut into pieces)
- 1 tablespoon Olive Oil (extra virgin, prevents butter from burning)
- 1 teaspoon Granulated Sugar (helps speed caramelization and adds color)
- 1 tablespoon All-Purpose Flour (for light thickening)
- 0.5 cup Dry Sherry (traditional deglazing liquid; can substitute cognac or dry white wine)
- 3.5 cups Beef Stock (homemade gelatinous stock; store‑bought works in a pinch)
- 2 teaspoons Fresh Thyme Leaves (fresh preferred)
- 0.25 teaspoon Salt (large pinch; adjust to taste)
- 2 each French Baguette (cut on an angle into ¾‑inch thick slices)
- 4 ounces Gruyère Cheese (grated)
- 2 ounces Fontina Cheese (grated)
- 2 ounces Swiss Cheese (grated)
Instructions
Prepare the onions
Peel the yellow onions, cut each in half top‑down, then slice into thin, uniform strips for even caramelization.
Time: PT10M
Caramelize the onions
Melt 4 Tbsp butter in the heavy pot over medium‑low heat, add the sliced onions, drizzle 1 Tbsp olive oil, sprinkle 1 tsp sugar, and cook, stirring occasionally, for about 1 hour until deep golden‑brown and sweet.
Time: PT1H
Add flour for light thickening
Sprinkle 1 Tbsp flour over the caramelized onions and stir for 2‑3 minutes until the flour loses its raw smell.
Time: PT5M
Deglaze with sherry
Pour ½ cup dry sherry into the pot, scraping the browned bits from the bottom with the wooden spoon; let simmer for 2 minutes.
Time: PT5M
Add stock, thyme and season
Stir in 3½ cups beef stock, 2 tsp fresh thyme leaves, and a large pinch of salt. Bring to a boil, then reduce heat to a gentle simmer and cook for 30 minutes.
Time: PT35M
Prepare bowls and cheese topping
Ladle the hot soup into oven‑safe bowls. Top each with a slice of toasted baguette and evenly distribute a total of 8 oz grated cheese mixture (Gruyère, Fontina, Swiss) – about 3 oz per bowl.
Time: PT10M
Broil the cheese
Preheat the broiler on high. Place the bowls on a rimmed baking sheet and broil for 3‑5 minutes, watching closely, until the cheese is melted, bubbly, and golden‑brown.
Time: PT5M
Temperature: Broiler high
Serve
Allow the soup to sit for a minute, then serve hot, optionally with a fresh baguette on the side.
Time: PT2M
Nutrition Facts
- Calories
- 380
- Protein
- 15 g
- Carbohydrates
- 30 g
- Fat
- 18 g
- Fiber
- 4 g
Dietary info: Contains beef, Contains dairy, Contains gluten
Allergens: Dairy, Gluten
Last updated: April 7, 2026






