Beurre Blanc Sauce (Classic French Butter Sauce)

What is Beurre Blanc?

Beurre blanc literally means "white butter" in French. It's a warm butter emulsion traditionally made by reducing finely chopped shallots with white wine vinegar, then gradually adding cold butter.

Today, dry white wine is also commonly used, giving the sauce its characteristic gentle acidity that cuts through all that butter. My version includes a little cream, which helps stabilise the sauce while allowing me to use less butter.

Unlike hollandaise or béarnaise sauce, beurre blanc contains no egg yolks.

Why is it also called Beurre Nantais?

According to many dictionary sources (such as French Larousse Gastronomique), beurre blanc is strongly associated with Nantes and the Loire, where it is also known as beurre nantais.

The most famous story credits Clémence Lefeuvre, with creating it around the end of the 19th century. While preparing béarnaise sauce for the local Loire river's pike (brochet), she forgot the egg yolks and tarragon - and Beurre Blanc was born.

Traditionally the sauce was made with shallots and vinegar; today dry white wine is usually included too. A Loire wine such as Muscadet is particularly good, although any good dry white works beautifully.

And don't stint on the vinegar. Alexandre Dumas - novelist, enthusiastic cook and author of the Grand Dictionnaire de Cuisine - specifically recommended a good vinaigre d'Orléans in his own shallot sauce à la Béarnaise. Read more about Alexandre Dumas' love of French cuisine and his extraordinary culinary dictionary.

Beurre Blanc with Less Butter

I originally posted this recipe with smoked tea in July 2011 for my John Dory recipe.

Since then, I've reduced the whopping amount of butter normally used for this French classic. Although cream is optional in beurre blanc, I add a little here to help the sauce thicken and stay stable while using less butter.

The result is still glossy, creamy and rich - rather like how I wish to be this year!

• For a smooth beurre blanc, strain out the shallots. Otherwise simply leave them in.
• Return the sauce to a very gentle heat before gradually whisking in the cold diced butter.
• Never let the sauce boil once the butter goes in.

The beurre blanc sauce is ready when it's glossy and lightly thickened and you can draw a line across the base of the pan with a spoon.

Do You Have to Strain Beurre Blanc?

No. Straining the shallots gives beurre blanc that classic silky, restaurant-smooth finish, but it's purely a question of texture.

I normally press the shallots through a sieve with the back of a spoon to extract as much flavour as possible.

However, when I made it again recently to serve with sea bass, I couldn't be bothered. I simply left the shallots in. The sauce wasn't quite as smooth, but it tasted every bit as good.

So strain it when presentation matters; leave the shallots in for the easier (and lazier) version.

What to Serve with Beurre Blanc Sauce

Beurre blanc is one of the classic French sauces for fish and seafood.

I recently served it over a fillet of sea bass (bar in French) and it was delicious. If you prefer cooking the fish whole, try my whole baked sea bass recipe and serve the sauce alongside.

It's also excellent with salmon, trout and delicate white fish such as John Dory (Saint-Pierre or St Peter fish). For something with a bit more texture, try it with herb-crusted salmon.

Keep the vegetables simple. Roasted asparagus, new potatoes, peas or sautéed green beans all work beautifully. The sauce is rich enough to do most of the showing off itself.

The good news is the sauce can be saved.
Heat 2 tablespoon cream in another saucepan (or heat in a bowl in the microwave) and vigorously whisk in the sauce gradually.

As the sauce freezes, it can also split if you defrost any frozen sauce directly in the microwave. So it's best to defrost it thoroughly at room temperature.

Can You Make Beurre Blanc Ahead?

Beurre blanc is best freshly made. If necessary, keep it warm for a short time over the lowest possible heat, but never let it simmer.

You can also cool leftover sauce and freeze it.

Defrost thoroughly before reheating, preferably at room temperature, then warm it very gently while whisking. Avoid reheating frozen beurre blanc directly in the microwave as the sudden heat can cause the sauce to split.

Beurre Blanc with Smoked Tea (Optional)

This is my Auld Alliance inspiration: saucy France meets Scottish salmon on a plate via a smoky Lapsang Souchong teabag.

Instead of adding the lemon juice sometimes found in beurre blanc, briefly infuse the sauce with smoked tea. Five minutes is enough to give it a subtle smoky flavour without overpowering the fish.

It's particularly delicious with salmon, although the smoked tea is completely optional. Leave it out for a classic beurre blanc.

Beurre Blanc Sauce with Watercress

One of my favourite variations came about after making a batch of our favourite French watercress soup.

Make the beurre blanc without the smoked tea, then stir in about 3-4 tablespoons of watercress soup at the end. It adds a fresh, peppery flavour and turns the sauce a lovely pale green.

It's particularly good with pan-fried salmon or white fish and basmati rice - or serve it with my herb-crusted salmon.