Butter Sauce

Ingredients

Equipment Needed

• •4-quart heavy-bottomed saucepan
• •2-quart saucepan for the salted water
• •Large balloon whisk
• •Medium heatproof bowl
• •Fine-mesh sieve
• •Flexible spatula
• •Instant-read thermometer, optional
• •Wide bowl for a cold-water bath

Instructions

1. 1

   Prepare the liaison

   Whisk the egg yolks, cream, and lemon juice in a heatproof bowl until completely smooth. Set this liaison within reach of the stove. Once the roux is loosened, the work moves quickly, and having the bowl ready is the home cook's honest equivalent of another pair of hands.

2. 2

   Cook the white roux

   Bring the water and salt just to the boil in a separate saucepan. Meanwhile, place the melted butter in a heavy 4-quart saucepan over medium-low heat and whisk in the sifted flour. Cook the roux for 2 to 3 minutes, whisking steadily, until it bubbles softly and loses its raw flour smell without taking any colour. This must remain a roux blanc, a white roux; browning it would change both the flavour and the ivory colour of the finished sauce.

3. 3

   Loosen the roux

   Take the roux from the heat and add one ladle of the boiling salted water, whisking briskly until perfectly smooth. Add the remaining water in four or five additions, fully smoothing each one before the next. Return the pan to low heat and stir briskly for 3 to 5 minutes, keeping the sauce hot but never boiling, until it lightly coats a spoon. If lumps appear, stop adding water and whisk the thick base smooth before continuing. Any stubborn specks will be caught by the sieve later.

4. 4

   Bind the liaison

   Whisk about 2 cups of the hot roux base into the liaison in a thin, steady stream. Take the saucepan off the heat, then slowly whisk the warmed liaison back into the remaining sauce. Return it to the lowest heat and stir constantly until it coats the back of a spoon and reaches about 160 to 165°F (71 to 74°C), with no bubbles breaking the surface. If it begins to look grainy, lift it from the heat immediately, set the pan over a bowl of cold water, and whisk until smooth. Ça se rattrape when caught early; boiling it into scrambled yolks cannot be undone.

5. 5

   Pass the sauce

   Press the sauce through a fine-mesh sieve into a clean warm saucepan or heatproof bowl, using a flexible spatula to work it through. This replaces the brigade's tammy without changing its purpose: removing any flour specks or traces of cooked yolk so the finish is perfectly smooth.

6. 6

   Monter au beurre

   With the sauce off the heat, whisk in the cool butter a few cubes at a time, waiting until each addition disappears before adding more. This is monter au beurre, whisking fresh butter into the sauce at the finish, and it supplies the sheen and rounded flavour the name promises. If the surface turns greasy, stop adding butter, cool the bowl briefly over cold water, and whisk firmly until the emulsion comes back together. Continue only when it is smooth again.

7. 7

   Hold without boiling

   Serve the Sauce au Beurre immediately, or hold it for no more than 30 minutes over a warm bain-marie at about 140 to 145°F (60 to 63°C). Stir occasionally and cover the surface directly with parchment so a skin cannot form. If it tightens, whisk in hot water a teaspoon at a time. Never return it to a boil. Spoon it generously over poached fish, boiled potatoes, asparagus, or cauliflower. À table!

Chef Tips

• •Use fresh unsalted butter with a clean, sweet flavour. Nearly half the character of this sauce arrives in the final mounting, so stale refrigerator butter announces itself plainly. Butter, not margarine. We don't apologize for butter.
• •A heavy saucepan buys you time because it spreads the heat evenly. A thin pan develops hot spots beneath the yolks, and one fierce patch can grain the sauce while the rest still looks calm.
• •Sauce au Beurre is gentler than beurre blanc and fuller than a plain white sauce. It belongs with quiet foods that welcome richness: poached white fish, steamed shellfish, asparagus, cauliflower, leeks, or boiled new potatoes.
• •This sauce waits poorly and reheats reluctantly. If you must warm it again, use a bain-marie and whisk constantly; direct heat risks splitting the butter or curdling the liaison.

Advance Preparation

• •Sift the flour, cube the finishing butter, and measure the water and salt several hours ahead. Keep the cubed butter cold, then let it lose its hard refrigerator chill while the roux cooks.
• •The yolks, cream, and lemon may be whisked together up to 30 minutes before cooking and kept cold. Bring the bowl beside the stove before loosening the roux.
• •For the best texture, finish the sauce shortly before serving. Leftovers may be chilled promptly and kept for up to 2 days, but reheat them only over a gentle bain-marie and expect a slightly heavier sauce.

Frequently Asked Questions

Nutrition Information

1 serving (about 62g)