How do you add eggs to thicken soup?

To add eggs for thickening soup, you must first temper egg yolks by slowly combining them with hot soup, whisking constantly, before incorporating the mixture back into the main pot.

How to Thicken Soup with Eggs

Using egg yolks is an excellent method to add richness and a silky texture to soups without making them heavy. The key to successfully thickening soup with eggs is a technique called tempering, which prevents the eggs from scrambling when they hit the hot liquid. This process gradually raises the temperature of the egg yolks, allowing them to blend smoothly with the soup.

Step-by-Step Guide to Tempering Egg Yolks for Soup

To effectively use egg yolks as a thickening agent, follow these steps based on the tempering method:

1. Prepare the Yolks: In a mixing bowl, whisk the egg yolks on their own until they are smooth and slightly frothy. The number of yolks needed will depend on the volume of soup and desired thickness, but generally, 2-3 yolks are sufficient for a medium pot of soup (around 4-6 servings).
2. Gradually Add Hot Soup: While continuously whisking the egg yolks, slowly ladle in hot soup bit by bit. It's crucial to add the hot liquid very gradually – just a tablespoon or two at a time initially – to slowly raise the temperature of the yolks without cooking them too quickly.
3. Whisk Constantly: Maintain constant whisking throughout this process. The continuous motion prevents the yolks from coagulating into lumps and ensures even heat distribution.
4. Reach Desired Temperature: Continue adding hot soup to the yolk mixture, whisking constantly, until the mixture is hot to the touch. This indicates that the yolks have been sufficiently warmed and are less likely to scramble when added to the main pot.
5. Incorporate into Main Soup: Once tempered, slowly pour the hot egg yolk mixture back into the main pot of soup, stirring gently.
6. Simmer Briefly (Optional): If desired, you can gently simmer the soup for a minute or two after adding the tempered eggs to allow the soup to thicken further, but avoid boiling vigorously, which can still curdle the eggs.

What is Tempering?

Tempering is a culinary technique used to gradually raise the temperature of a cold or room-temperature ingredient, such as eggs or dairy, by slowly adding a hot liquid. This prevents the ingredient from cooking too quickly (like scrambling eggs) and allows for a smooth incorporation into a hot dish, ensuring a consistent texture and preventing curdling.

Tips for Success

• Use Egg Yolks Only: While whole eggs can be used, egg yolks provide a richer flavor and superior thickening power due to their higher fat content.
• Whisk Thoroughly: Vigorous whisking during the tempering process is critical to prevent curdling and achieve a smooth consistency.
• Don't Boil: After adding the tempered egg mixture, avoid bringing the soup to a rolling boil, as this can still cause the eggs to curdle or separate. A gentle simmer is usually sufficient for further thickening.
• Strain for Smoothness: For an ultra-smooth soup, you can optionally strain the tempered egg mixture before adding it back to the main pot, or strain the entire soup at the end.
• Adjust Thickness: If the soup isn't thick enough, you can repeat the process with a smaller amount of additional egg yolks, or use another thickening agent like a cornstarch slurry.

Do's and Don'ts for Thickening Soup with Eggs

Using tempered egg yolks is an effective way to impart a luxurious, creamy texture to your favorite soups, transforming them into a more satisfying and comforting meal.