Julia Child Cream of Mushroom Soup (Soup Recipe)

This smooth, pale, mushroom-forward soup starts with mushrooms gently cooked in butter and lemon, then thickened with flour and hot stock. Egg yolks and cream give it a rich finish. Use a heavy-bottomed, nonreactive saucepan, simmer the base for about 20 minutes, and keep the finished soup below a boil to help prevent curdling.

Julia Child helped bring French cooking into home kitchens through her books and television show The French Chef. This soup follows that spirit: a clear sequence of steps, familiar ingredients, and careful attention to heat. The proportions below are a representative Julia Child formulation; recipes can vary by edition.

Ingredients and recipe at a glance

This is a stovetop cream of mushroom soup built from a short list of measured ingredients. The method first cooks mushrooms in butter and lemon, then thickens stock with flour. Egg yolks and cream go in at the end, so the soup finishes smooth and rich.

Use a mild chicken stock or mushroom stock. A strongly flavored stock can cover the mushrooms, while a very salty stock may make the finished soup too salty. Taste before adding much salt.

Have the ingredients measured before you start. Once the flour is in the pan, gradual whisking matters more than speed, and the final egg-and-cream mixture needs your attention.

Cookware Compatibility, Materials & Preparation

The right saucepan makes it easier to control heat and stir the thickening soup without scorching it. Choose a heavy-bottomed stainless-steel or enamel-lined pan, or lined copper. For induction, the pan needs a magnetic base; unlined reactive copper or aluminum is not a good match for lemon juice.

A heavy base spreads heat more evenly than a thin one, which helps reduce hot spots as the stock simmers. Stainless steel and enamel-lined cookware also suit the lemon in this recipe. If you use copper, choose a lined pan and follow the maker’s care instructions.

Set the pan over low to medium heat. Melt the butter gently; it should melt without browning or smoking. Slice the mushrooms to a similar thickness so they soften at roughly the same rate. Wipe off visible dirt with a damp cloth or paper towel, then dry them before slicing.

Mushroom Soup Technique & Execution

The key technique is to build a smooth, flour-thickened base before adding the egg-and-cream finish. Cook the mushrooms gently for a pale soup, whisk in hot stock in stages, and let the base simmer long enough to lose its raw-flour taste. Finish over low heat and do not boil.

1. Soften the mushrooms. Melt the butter in the prepared saucepan over low to medium heat. Add the sliced mushrooms and lemon juice. Stir and cook gently until the mushrooms are tender and have released some moisture. Keep the heat moderate; browning is not needed for the classic pale appearance.

2. Cook the flour. Sprinkle the flour over the mushrooms and stir until it coats them. Cook briefly, stirring, so the flour blends with the butter. Do not let the mixture brown if you want a pale soup.

3. Add the stock gradually. Pour in a small amount of hot stock while whisking to make a smooth paste. Continue adding the stock in several additions, whisking as you go. This gradual approach helps limit lumps. Scrape the base and corners of the pan as you stir.

4. Simmer the base. Bring the soup to a gentle simmer, then lower the heat. Simmer for about 20 minutes, stirring now and then so the thickened mixture does not stick. A gentle simmer has small, occasional bubbles rather than a hard, rolling boil.

5. Temper the yolks. Beat the egg yolks in a heat-safe bowl. Slowly whisk in a ladleful of hot soup, a little at a time. This step, called tempering, warms the yolks gradually so they are less likely to form curds when added to the pan.

6. Add the cream and finish. Whisk the cream into the tempered yolks. Stir this mixture into the saucepan over low heat. Keep stirring until the soup is steaming and lightly thickened. Do not let it boil: high heat can curdle the yolks and cream, leaving a grainy texture. Taste and add salt and pepper as needed.

Serve the soup with the mushroom slices as they are, or blend it if you prefer a smoother texture. Blending is optional; the recipe does not require a special tool. If using a countertop blender, follow its instructions for hot liquids.

Cleaning, Cooling & Cookware Care

After serving, handle leftovers with food safety in mind. Cool the soup promptly in shallow containers, then refrigerate it. For reheating, U.S. FDA Food Code benchmarks call for reheating previously cooked soup to 165°F (74°C) for 15 seconds and holding hot food at or above 135°F (57°C); these are food-safety benchmarks, not recipe cooking targets.

For the smoothest make-ahead result, you can prepare the mushroom-and-stock base first and add the tempered yolks and cream when you finish the soup. If the finished soup is already made, stir it as you reheat it over low heat. Use a food thermometer to check the reheating temperature, and avoid bringing it to a boil.

Let the saucepan cool enough to handle safely before washing it. Use the cleaning method recommended for its material, especially for enamel or lined copper. Avoid abrasive tools if the cookware maker advises against them.

Serving, Garnish & Dining Presentation

This soup is rich enough to serve in modest portions as a first course or in larger bowls as a light meal. Keep the garnish simple so the mushroom flavor stays in front. Serve it soon after finishing, while it is hot and the texture is smooth.

A few sliced, gently cooked mushrooms make a direct garnish. Chopped parsley can add color, while a small swirl of cream echoes the finish. Toast or plain bread works well alongside the soup; add it at the table rather than into the pan so the soup keeps its texture.

If the soup thickens as it stands, stir in a little hot stock or water until it reaches the consistency you like. Add liquid in small amounts and taste again before adjusting the seasoning.

Frequently Asked Questions

These quick answers cover common ingredient, texture, and storage questions about this mushroom soup. The main points are simple: keep the mushroom base pale if that is your preference, add the stock gradually, and protect the yolk-and-cream finish from boiling heat.

Is this an exact Julia Child recipe?
Recipes can vary by edition. The ingredient amounts here are a representative formulation, not a claim that every version is identical.

What mushrooms work best?
White button or cremini mushrooms are practical choices. Slice them evenly so they soften at a similar pace.

Can I use vegetable stock?
Yes. Choose a mild vegetable stock so it supports, rather than masks, the mushroom flavor.

Why add lemon juice?
It is part of the representative formulation and brings brightness to the butter-cooked mushrooms. Use the measured amount in the recipe.

How do I keep the soup smooth?
Whisk in hot stock gradually, simmer the base, and temper the yolks with hot soup before adding the cream mixture.

Can I skip the egg yolks?
You can leave them out, but the finished soup will not have the same yolk-enriched texture. Keep the flour-thickened base and cream in mind when adjusting the recipe.

Can I make it ahead?
Yes. For a more controlled finish, make the mushroom-and-stock base ahead and add the tempered yolks and cream when you reheat and finish the soup.

Can I freeze the finished soup?
The texture of a cream-and-yolk soup may change after freezing and thawing. For a smoother result, freeze the base before adding the yolks and cream, then finish it after thawing.

Why did my soup curdle?
The yolk-and-cream mixture may have become too hot. Add it over low heat and do not boil the soup afterward.

How should I reheat leftovers?
Reheat while stirring, and check that the soup reaches 165°F (74°C) for 15 seconds. Keep the heat gentle to avoid boiling the soup.

(This article was written by one of our staff writers, Steven R. Bancroft. Visit our Meet the Team page.)