It looks so simple when Megan Lambert does it. Make cake. Cover it with fluffy filling. Roll cake. Drape with melted chocolate. Decorate with meringue mushrooms.
Place it on your Christmas table and knock people’s Christmas stockings clean off.
Making a traditional French Buche de Noel, or Yule Log Cake, actually is simple. It takes a few steps, but you can spread them out over a few days.
Still, like all things in baking, it helps to know a little science and a few tricks. Lambert, 35, knows both. She’s a pastry instructor at Johnson & Wales University in Charlotte with a registered dietitian background. She’s also teaches baking science, things like what happens when you beat air into eggs and why potato starch keeps cakes moist and flexible.
We asked Lambert to take us through the steps of a Buche de Noel. But first, we asked her to explain the cake:
“It came from an ancient pagan ritual,” she says. People used to burn a log as an offering for the winter solstice. The French kept the custom when the solstice holiday became Christmas.
Unfortunately, log-burning didn’t work so well in Paris apartments. Burning Yule logs was eventually outlawed. To keep the tradition, people started putting a log on the Christmas table and decorating it.
“Being French, they said, ‘Why are we using a real log? Let’s use something that tastes good.’” So people started decorating a rolled-up cake to look like a log.
“If you look on (baking) Web sites in France, they’re making really elaborate ones,” including layered cakes molded in terrine pans and variations with different flavors of cake and filling, such as vanilla cake with lemon curd or chocolate with raspberry jam. For us, Lambert kept it traditional, with a chocolate cake, chestnut rum filling, and chocolate ganache icing.Cake
Although a genoise (butter-based sponge) is traditional for rolled cakes, Lambert prefers an easier roulade, or sponge cake. It doesn’t involve folding in beaten egg whites and it uses potato starch, which adds moisture and flexibility. It also doesn’t use butter, so it’s very light.
She starts by beating the eggs and sugar to make a ribbon. Lambert whips them on high speed at first, to build in lots of air, then reduces the mixer to medium to stabilize the batter.
“Watch one spot,” she says. “It keeps going up and then it just starts going back down,” leaving a little mark around the top of the bowl. “That’s full volume.”
To check for the ribbon, lift a spoonful and let it pour back into the bowl – it should fall in a fold that holds its shape for a few seconds. Or run your finger over the back of the spoon – it should leave a track.
After beating the eggs and sugar, she adds potato starch, cake flour, baking powder and Dutch-process cocoa by thirds, shaking the mixture through a sieve, then folding in each addition with a rubber spatula.
She teaches her students to fold – lifting the batter with the spatula to add the dry ingredients without deflating the eggs – by working from the center out. If you go from the outside in, you tend to just go around the edge and never reach the center.
Lambert spreads the batter in a 16-by-12-inch sheet pan that’s lined with waxed paper. If you only have a 13-by-9-inch pan, use the extra batter to make cupcakes. You can use them as “stumps” around your Yule log.Filling
Lambert was a little shocked when a can of chestnut puree at a local gourmet shop was $8.50. “But it’s worth it,” she says. For the filling, she beats the chestnut puree with dark rum and folds in whipped cream. She also makes a rum-flavored simple syrup to brush the cake, adding moisture and flavor. After brushing on the syrup, she spreads the cake with a layer of filling, about 1 inch thick. Don’t get carried away – if the filling is too thick, it’s harder to see the rolled center that makes the cake look like a cut log.Mushrooms
It’s traditional that everything on the Yule log is edible. For the meringue mushrooms, Lambert prefers a very simple version made from beaten egg whites, sugar and cream of tartar for stability.
Wait until the egg whites are foamy before beating in the sugar and cream of tartar. Then just let the mixer go – the more air you beat in, the whiter it will be.
She pipes out two shapes: First, a tall row, holding the pastry bag straight down, lifting up and stopping the pressure. That makes stubs that look like finger tips. Then a flat row, holding the tip low on the pan, squeezing, releasing and lifting the tip with a swirl. That makes discs.
She shakes cocoa over the tops to look like the brown spots on mushrooms, then puts the pan in a very low, 200-degree oven, turns off the heat and leaves it overnight to dry. She trims the tip from a stubby shape with a paring knife, then brushes the underside of a disc with melted chocolate.
Put the disc on the stub and you have a mushroom, with the chocolate looking like gills.
“They don’t have to be perfect,” she says. “They’re mushrooms.”Rolling
You need parchment paper for this, and you need a piece that is larger than the cake. Turn the cake pan upside down, whacking it if needed, and lay the cake on the parchment. Peel away the waxed paper, brush the cake with simple syrup and spread it with the filling.
Next, get a yardstick and have it handy. Start from the long side of the cake. Use the parchment paper to lift the edge of the cake and fold it over. Use the yardstick to press in the edge, getting it as tight as you can. Lift the paper and turn the cake over again.
“Lift down with the paper, not up,” Lambert says. That keeps the edge pressing in tight. When you get to the other side, roll it back toward you to wrap it up in the paper. Twist the ends tight and refrigerate the cake, to firm up the filling.Decorating
Now, the fun part. Many recipes use buttercream, but Lambert likes ganache, a simple chocolate coating made by pouring hot cream over chopped chocolate. Use good-quality chocolate, at least 55 percent cacao (but no higher than 65 percent or it will be too bitter). Lambert adds a little corn syrup to make it shiny, and lets it stand at room temperature overnight to set up. Rewarm it a little if it’s too stiff to spread.
Unroll the cake from the parchment paper and place it on a serving tray. Cut off 2 or 3 inches from each end at an angle, then place those pieces against the edges of the cake. That makes a cut log with two trimmed-off branches.
Spread the cooled ganache over the cake with a metal spatula, leaving flat ridges to simulate tree bark. You also can draw fork tines through it. Leave the ends uncovered so the spiral of cake and filling look like tree rings.
Press meringue mushrooms into the chocolate quickly, before it sets. “I always use too many mushrooms,” Lambert jokes.
She tucks a few rosemary sprigs around the cake for pine boughs, then adds a few fresh cranberries for the holly-berry look. A quick sift of confectioner’s sugar over the top for snow and that’s it:
A finished Yule Log. Good enough to eat.Recipes:
From Megan Lambert, pastry instructor, Johnson & Wales University, Charlotte.
Steps to a delicious yule log
Cake: Chocolate Roulade Sponge Cake 5 large eggs 3/4 cup sugar 1/2 cup potato starch 3 tablespoons cake flour, such as Swansdown 3 3/4 teaspoons baking powder 3 tablespoons Dutch-process cocoa powder
Preheat oven to 375 degrees. Cut a piece of parchment or wax paper to fit a 16-by-12-inch sheet pan or jellyroll pan (or the closest size you have). Place the eggs in the bowl of a stand mixer fitted with the whip attachment. Begin whipping on high speed. Sprinkle in the sugar while the eggs are whipping. Whip until the mixture reaches full volume; it will climb up the side of the bowl and just begin to climb back down. Reduce mixer to medium speed and beat 4 to 6 minutes, to stabilize it so it doesn’t deflate when you fold in the dry ingredients. Remove the mixing bowl from the mixer. Place the starch, flour, baking powder and cocoa powder into a sifter. Sift about 1/3 of the dry mixture on top of the egg mixture. Gently fold in the dry ingredients until almost mixed in, and then sift on another 1/3 of the dry ingredients. Continue to gently fold and sift the final 1/3 of the dry ingredients. Fold just until the dry ingredients are incorporated and no streaks are visible. Spread the batter gently into the prepared pan until smooth. The batter should fill the pan about halfway. Bake the cake for 12 to 15 minutes, until it springs back when you touch it lightly in the center. If you leave a fingerprint, bake it a few more minutes. Cool completely before removing from the pan. Can be made the night before you need it.Filling: Rum Simple Syrup 1/2 cup sugar 1/2 cup water 1 ounce dark rum
Bring sugar and water to a boil in a small saucepan. Cool and add the rum. Can be made several days in advance and refrigerated.Chestnut Rum Cream Filling
This is enough filling for two buche de noel. The thinner you spread the filling, the more rings your log will have. If you use more filling, it will have fewer rings, but more delicious rum chestnut filling. If you want to divide the recipe in half, use the remaining chestnut spread as a crepe filling or an ice cream topping. 1 (17.5-ounce) can sweetened chestnut spread (available at gourmet food stores such as Dean & Deluca) 2 ounces dark rum 1 pint heavy whipping cream
Whip the heavy cream to medium stiff peaks, by hand or with a mixer. Refrigerate until needed. Mix the rum into the chestnut spread with a rubber spatula. Gently fold the whipped cream into the chestnut-rum mixture in two or three additions, mixing just until there are no visible streaks. Refrigerate until needed.Chocolate Ganache 1 cup heavy or whipping cream 1 tablespoon corn syrup 8 ounces semisweet chocolate, with 55 to 65 percent cacao
Chop the chocolate and place in a bowl. Combine the cream and corn syrup in a saucepan and bring a boil. Pour the hot cream over the chocolate, and let stand a few minutes. Whisk the mixture together until smooth and shiny. Place a piece of plastic wrap directly on the surface to prevent formation of a skin. Let stand overnight at room temperature to set up.Mushrooms: Mushroom Meringue 3 large egg whites 1/8 teaspoon cream of tartar 3/4 cup sugar 2 tablespoons Dutch-process cocoa powder 1/4 cup semisweet chocolate chips
Place the egg whites into the bowl of a stand mixer fitted with a whip Begin whipping on high speed, and add the cream of tartar. Continue whipping on high speed until the whites form soft fluffy peaks. While continuing to whip the egg whites, slowly and steadily sprinkle in the sugar. Continue to whip 5-10 minutes longer, until the meringue until very white and stiff. Place the meringue into a piping bag fitted with a round, 3/8-inch tip. Line a sheet pan with parchment paper. Pipe out the mushroom stems and caps as directed. Sift a little cocoa powder over the caps. (Try to hit just one side of the caps rather than covering them.) Use a hand-held fan (or a quickly exhaled breath) to blow off the excess cocoa powder. (Be careful not to inhale the cocoa powder.) Place the mushrooms into a 200-degree oven. Turn off the oven and leave overnight, until completely dry, crisp and still very white. (Note: If the oven is too hot when the mushrooms go in, they will puff, crack and caramelize. They’ll still be delicious, but won’t look so pretty.) Cut the pointy ends off the stems to make a flat surface. Melt the chocolate chips carefully in the microwave. Dip the bottom of a mushroom cap in the chocolate. Place on the stem and stand the mushrooms up to let the chocolate set.