NPR logo Cracking The Egg Code

Cracking The Egg Code

Kevin D. Weeks for NPR
A copper bowl holds eggs dyed in bright colors
Kevin D. Weeks for NPR

Perfect Hard-Boiled Eggs

Anyone who has hard-boiled eggs has had experience with overcooked eggs and that nasty green ring around the yolk (a result of sulfur compounds in the egg). And undercooked eggs with slightly runny yolks are no better. As Ralph Waldo Emerson observed, "There is always a best way of doing everything, if it be to boil an egg." In fact, there is a best way to boil an egg.

1. Place eggs in a single layer in the bottom of a saucepan.

2. Cover with water to a depth of 1 inch.

3. Bring water just to a boil over medium-high heat.

4. Remove from heat, cover and let sit for 17 minutes.

5. Cool eggs in an ice-water bath to stop the cooking.

6. Once cooled, peel.

About The Author

After working as editor of various computer magazines, Kevin Weeks is now a personal chef in Knoxville, Tenn. He specializes in cooking with a Mediterranean accent, filling plates with the flavors of southern Europe and northern Africa. Weeks also teaches cooking classes and blogs at Seriously Good.

Celebrations of spring — both religious and secular — almost always include eggs. These symbols of creation, fertility and rebirth are also extraordinary little nutrition packages, and are present in many of the things we eat.

The average large chicken egg provides 75 calories and 6.3 grams of protein in addition to calcium, iron, potassium, phosphorus and zinc. An egg also has about 5 grams of fat and 200 milligrams of cholesterol.

Is that too much cholesterol — the source of the egg's unhealthy rep? Probably not. Most cholesterol is produced in our own bodies, and although there is a correlation between high cholesterol levels and increased risk of heart attack, there's no direct causative link between cholesterol from outside sources and heart disease. Eating six eggs for breakfast every day is probably excessive, but eating a couple of eggs on occasion won't hurt.

With the exception of protein, most of an egg's nutrition is contained in the yolk, which contains three quarters of the calories and most of the nutrients. The white, on the other hand, is mostly water (one of its purposes is to provide water to the growing embryo) and proteins. The white also serves as a cushion protecting the yolk/embryo and has both antibacterial and antiviral characteristics. In fact, an egg that hasn't been contaminated before the shell forms will keep safely for two or three days without refrigeration and as long as a month if refrigerated.

Eggs are one of the few foods in Western cuisine that play an equal role in both sweet and savory dishes. Custards in the form of a quiche are typically savory, but custards are also sweetened to make pots de creme or flans. Souffles, too, may be sweet or savory. Eggs also add richness and texture to sweet (lemon curd) and savory (hollandaise) sauces.

Despite assertions to the contrary, the color of an egg's shell indicates nothing about its content and is determined by the hen's breed. Whether brown, white or blue-green on the outside, eggs are nutritionally the same, and flavor is primarily a function of freshness and the hen's diet. However, it is true that old eggs will float while fresh eggs will sink in fresh water. It's also true that older eggs are easier to peel when hard-boiled than fresh eggs.

There is a lot of lore associated with the egg, in addition to its role as a symbol of spring. In Chinese mythology, the universe began as an egg containing the god Pangu; and in Finnish myths, the world was created from fragments of duck egg. Eggs also feature in the creation stories of other cultures around the world from Africa to Polynesia.

And if you've ever wondered which came first, eggs existed long before chickens evolved. In fact, novelist Samuel Butler noted that "chickens are an egg's way of making more eggs."

Tuna-Stuffed Eggs

Kevin D. Weeks for NPR
Tuna Stuffed Eggs
Kevin D. Weeks for NPR

The Spanish are well-known for their small appetizer plates called tapas. The Greeks call theirs mezethes and put their own special culinary stamp on them. One of my favorite meze are eggs stuffed with tuna. This version makes a nod to Spain by incorporating Spanish paprika (pimenton). The smoky flavor of the paprika complements both the tuna and the egg while adding an American devilish note to the affair.

Makes 24 stuffed eggs

12 large hard-boiled eggs, shelled and cut in half

1 6-ounce can oil-packed tuna

4 tablespoons finely chopped red onion

4 tablespoons mayonnaise

2 tablespoons Dijon mustard

4 teaspoons lemon juice

1/4 teaspoon salt

3/4 teaspoon smoked hot Spanish paprika

Remove egg yolks and set whites aside. In a small bowl, beat yolks together with all other ingredients until smooth. Spoon into hollowed-out egg whites. Chill and serve.

Provencal Souffle

There's little hint in the finished souffle that a savory tomato sauce awaits at the bottom. Kevin D. Weeks for NPR hide caption

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Kevin D. Weeks for NPR

There's little hint in the finished souffle that a savory tomato sauce awaits at the bottom.

Kevin D. Weeks for NPR

Each serving of Provencal souffle is infused with tomato and herbs, prosciutto and cheese. Kevin D. Weeks for NPR hide caption

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Kevin D. Weeks for NPR

Each serving of Provencal souffle is infused with tomato and herbs, prosciutto and cheese.

Kevin D. Weeks for NPR

I've loved souffles for as long as I can remember. My mother made them fairly often when I was a child, and I recall a feeling of wonder at the way they puffed and browned, magically becoming a toasted yellow mushroom. I also experienced with wonder their ethereal texture and the rich goodness of egg and cheese, flavors somehow transformed to something better. This souffle features a tomato sauce on the bottom that suffuses the souffle as it cooks and provides a delicious sauce. It's been my mother's favorite since I first made it.

Makes 4 servings


2 tablespoons olive oil

1/4 cup carrots, finely diced

1/4 cup celery, finely diced

1/4 cup onion, diced

Salt to taste

1 teaspoon dried herbes de Provence

1 large clove garlic, minced

1/4 cup white wine or vermouth

1 15-ounce can diced tomatoes

Pinch crushed red pepper


3 tablespoons unsalted butter (additional butter to grease dish)

1/4 cup finely grated Parmesan

2 ounces prosciutto, about 1/8-inch thick

3 tablespoons unbleached flour

1 teaspoon ground mustard

1 cup whole milk, at room temperature

1 teaspoon salt

1 teaspoon white pepper

4 large egg yolks

1/2 cup shredded comte, gruyere or manchego

4 large egg whites, at room temperature*


Heat oil in a skillet over medium heat. Add carrots, celery, onion, salt and herbs and saute until softened. Add garlic and cook another minute. Add wine and increase heat to medium high. Reduce wine by half and add tomatoes, including juice. Continue cooking, stirring occasionally, until most liquid has evaporated. Taste, adjust seasoning and allow to cool.


Heat oven to 425 degrees. Grease a 2-quart souffle dish with butter and dust with Parmesan.

Mince prosciutto until very fine in a food processor.

Melt the butter over medium low heat, add flour and cook for 5 minutes, stirring constantly. Mix in mustard. Add milk, and continue stirring until thickened. Add salt and pepper. Add in yolks, one at a time, whisking constantly to prevent the yolks from curdling. Stir in cheese and melt. Add prosciutto and mix thoroughly. Remove from heat and allow to cool to room temperature.

Beat egg whites to medium stiff peaks. Thoroughly fold 1/3 of whites into sauce mixture. Fold mixture back into remaining whites. Pour tomato sauce into bottom of souffle dish. Pour souffle mixture on top, place in oven and bake 10 minutes.

Reduce heat to 375, and continue to bake for a total of 40 to 45 minutes, depending on how well done you like your souffles. Don't open the oven for the first 20 minutes.

*Eggs are easier to separate when cold, but egg whites whip better at room temperature.

Cheshire Cheese Quiche

Kevin D. Weeks for NPR
Cheshire Cheese Quiche
Kevin D. Weeks for NPR

A friend, Q Correll, came up with the idea of using cheshire cheese in a quiche. I don't know why, but it makes the lightest, fluffiest quiche I've ever had. The quiche is best straight out of the oven, when it's at its airiest, but it's also good left over.

Makes 6 servings

2 slices (1/4-inch-thick) pancetta (3 ounces), cut into 1/4-inch dice

1 medium leek, washed and coarsely chopped

1/2 pound cheshire cheese, shredded

1 1/2 cups half-and-half

3 large eggs

1/2 teaspoon powdered mustard

1/2 teaspoon salt

1/4 teaspoon white pepper

Dash of cayenne

9-inch pie crust

Heat oven to 375 degrees.

Cook pancetta in a skillet over medium heat until it begins to render its fat, 3 to 4 minutes. Add chopped leeks and saute until translucent.

Combine cheese, pancetta and leek in bowl, then scoop into pie shell. Whisk together remaining ingredients and pour into pie shell. Cook on middle rack of oven for 45 minutes or until center is set.

Key Lime Mousse

Kevin D. Weeks for NPR
Key Lime Mousse
Kevin D. Weeks for NPR

Those tiny little key limes can be a pain to juice. But several years ago, a Cooks Illustrated reader suggested using a garlic press to squeeze the juice out, and it works perfectly. Cut a lime in half, place it in the press and bear down. It takes some time, but once you've used real key limes in a recipe, you won't go back to the large Persian limes. This recipe is a delightful spring treat but is equally good after eating barbequed ribs in July.

Makes 6 servings

1 package unflavored gelatin (1/4 ounce)

3 tablespoons warm water

4 large egg yolks

2/3 cup fresh key lime juice (16 to 20 key limes)

3/4 cup sugar, divided

2 tablespoons lime zest

1/4 teaspoon vanilla extract

3 large egg whites, at room temperature*

1 cup whipping cream

Sprinkle gelatin over warm water and set aside to soften.

Whisk yolks in a small saucepan to blend. Then whisk in lime juice, 1/2 cup sugar and lime zest. Cook over low heat, stirring constantly, until mixture thickens to the consistency of heavy cream. Remove from heat and stir in gelatin and vanilla extract.

Set pan in cold water and cool to room temperature, stirring occasionally.

Beat egg whites until soft peaks form.

In another large bowl, beat whipping cream until soft peaks form, add remaining 1/4 cup sugar and beat until stiff.

Fold egg whites into whipped cream. In increments of 1/3, fold lime mixture into whites and cream. You can either divide the mixture into 6 individual serving dishes or leave in the large bowl. Chill until set.

* Eggs are easier to separate when cold, but egg whites whip better at room temperature.