Daring Bakers and the Filbert Gateau with Praline Buttercream

Another month, another Daring Baker challenge. This month, Chris from Mele Cotte chose a Filbert Gateau with Praline Buttercream from Great Cakes by Carol Walter. I'm familiar with Walter from Great Cookie, but I haven't looked at her other cookbooks. After looking through the ingredient list a couple hundred times, I put this challenge off because it seemed pretty comparable to May's challenge, the Opera cake. So, come Tuesday, I finally got to it and completed the challenge. In one day. Many hours in a row. Do not follow my example.

Almond-Flour Mixture

After toasting the almonds and processing them with the genoise's dry ingredients, I kept smelling the mixture until I figured out what it reminded me of: French fries! Not exactly the most appetizing of smells, especially for a cake.

Almond Genoise Batter

Of the three sponge cake recipes I've made with the Daring Bakers, this one I made perfectly. There was no separation of the almond meal from the liquid mixture, and it seemed to rise well. I actually did not mean to clarify the butter, but I forgot it was on the stove, so I ended up needing to separate the solids. My aim was just to brown the butter. Since I didn't have any lemons, I used grated orange rind.

Baked

Moist and pillowy, I was pleased with the results. The skins left on the bottom of the cake pans were delicious.

Almond Praline

What you see above is the result of my first successful attempt at a straight caramel, meaning I didn't add water. Usually there are lumps of sugar that never dissolve (from when recipes call to add the water after the sugar caramelized), and I was wary about not adding water to the sugar before it caramelized, but it worked out. After I added the toasted almonds, I let the mixture remain on the heat a bit too long, so the combination of the toasted almonds with the caramelized sugar was almost bitter, but it tasted great. I could have eaten this without having pureed to a paste, but that would have defeated the purpose.

Praline Buttercream

Carol Walter's directions for this buttercream were a bit unnecessary. Adding the sugar separately? Little by little? Dorie Greenspan's Swiss meringue buttercream from April's challenge didn't call for it and I think hers was even better. But anyway, this worked out well, emulsified after whipping, though it was soft at the end (unlike Greenspan's) and required refrigeration before icing. It tasted great, almost like a Butterfinger with a hint of kirsch (the liquor I used for the icing, the simple syrup, and the ganache).

Makeshift Cake Board

This is my MacGyver adaption of a cake board. I cut the rim off of an old shortening lid, then covered it in wax paper. Not as sturdy as cardboard, but it gets the job done.

I Iced the Gateau

1. Brush the cake layers with simple syrup
2. Spread with a thin layer of praline buttercream
3. Spread whipped cream on top of the buttercream
4. Top with the remaining layer and crumb coat with the buttercream. Chill.

The Chocolate, the Ganache

This is the block of Callebaut that I kept forgetting I had.

That is the ganache that I did not allow to thicken enough before pouring over the cake. After letting the first coating set, I poured the ganache on top. They say the third time's the charm, but by this time I had been baking for a few hours straight, it was getting late, and I said forget it.

The Featured Production

After the ganache had completely set and the cake had been decorated with the remaining buttercream, you couldn't really see the mistakes that well. The cake sliced beautifully and the definition of the layers was quite apparent. Furthermore, each layer of filling was just about even, something which I usually mess up slightly.

The final verdict was that it didn't seem very spectacular, and really wasn't much different than the Opera cake challenge. I couldn't taste the praline buttercream through the other ingredients, and the ganache layer wasn't even thick. While I enjoyed this challenge and some of the different components separately, it just didn't impress me for all the work that was involved.

The End

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Filbert Gateau with Praline Buttercream
From Great Cakes by Carol Walter, rewritten for clarity by Dulcedo
(I cut the entire recipe in half, minus the exemption of the apricot glaze, and used three 6-inch pans)

Yields one 10" cake

Sugar Syrup
1 cup water
1/4 cup sugar
2 tablespoons dark rum or Grand Marnier

Filbert Genoise
1 1/2 cups hazelnuts, toasted and skinned
2/3 cup cake flour
2 tablespoons cornstarch
7 egg yolks
1 cup sugar, divided
1 teaspoon vanilla extract
1/2 teaspoon grated lemon zest
5 egg whites
1/4 cup warm, clarified butter (100 – 110 degrees)

Praline Paste
1 cup hazelnuts, toasted and skinned
2/3 cup sugar

Praline Buttercream
4 egg whites
3/4 cup sugar
1 1/2 cups (3 sticks) unsalted butter, slightly firm
2 tablespoons Grand Marnier
1 teaspoon vanilla
1/3 cup praline paste
2 tablespoons dark rum

Apricot Glaze
2/3 cup thick apricot preserves
1 tablespoon water

Ganache Glaze
6 ounces good semisweet or bittersweet chocolate
3/4 cup heavy cream
1 tablespoon light corn syrup
1 tablespoon dark rum or Grand Marnier
3/4 teaspoon vanilla

To Make the Sugar Syrup:
In a small, heavy saucepan, bring the water and sugar to a boil and simmer for 5 minutes. Remove from heat and add the liqueur. Cool slightly before using on the cake. Can be made up to 1 week in advance and stored, covered, in the refrigerator.

To Make the Filbert Genoise:
Preheat to 350 degrees F. Grease and flour a 10” X 2” inch round cake pan.

Using a food processor, process nuts, cake flour, and cornstarch for about 30 seconds. Then, pulse the mixture about 10 times to get a fine, powdery mixture. You’ll know the nuts are ready when they begin to gather together around the sides of the bowl. While you want to make sure there aren’t any large pieces, don’t over-process. Set aside.

Put the yolks in the bowl of an electric mixer. Beat with the whisk attachment on medium-high speed until thick and light in color, about 3-4 minutes. Slowly add 3/4 cup of sugar, one tablespoon at a time (this step should take about 3 minutes). When finished, the mixture should be ribbony. Blend in the vanilla and grated lemon rind. Transfer to a separate bowl and set aside. Wash and thoroughly dry the mixer bowl.

Place egg whites in the clean mixer bowl and beat with the whisk attachment on medium speed until soft peaks form. Increase the speed to medium-high and slowly add the remaining 1/4 cup of sugar over 15-20 seconds. Continue to beat for another 30 seconds. Add the yolk mixture to the whites and whisk for 1 minute.

Working quickly and excluding any large chunks, sprinkle the processed nuts into the egg mixture 2 tablespoons at a time, folding carefully for about 40 folds. When all but about 2 tablespoons of nuts remain, quickly and steadily pour the warm butter over the batter. Add in the final 2 tablespoons of nuts and fold the batter to incorporate, about 13 folds.

Transfer the batter into the prepared pan. (If collected butter remains at the bottom of the bowl, do not add it to the batter.) Tap the pan on the counter to remove air bubbles and bake in the preheated oven for 30-35 minutes. You’ll know the cake is done when it is springy to the touch and it separates itself from the side of the pan. Remove from oven and allow to stand for 5 minutes before inverting on a wire rack to cool completely.

[If not using the cake right away, wrap thoroughly in plastic wrap, then in a Ziploc bag, and store in the refrigerator for up to 3 days. If freezing, wrap in foil and then place in the bag; use within 2-3 months.]

To Make the Praline Paste:
Line a jelly roll pan with parchment paper and lightly butter.

Put the sugar in a heavy 10" skillet. Heat on low flame for 10-20 minutes until the sugar melts around the edges. Swirl the pan if necessary to prevent the melted sugar from burning, but do not stir. Brush the sides of the pan with water to remove sugar crystals.

When the sugar is completely melted and caramel in color, remove from heat. Stir in the nuts with a wooden spoon and separate the clusters. Return to low heat and stir to coat the nuts on all sides. When the mixture starts to bubble, remove from heat and pour evenly onto the parchment-lined sheet. As it cools, it will harden into brittle.

Break the cooled brittle into pieces and place in a food processor. Process for several minutes to make a paste. Store in an airtight container in a cool, dry place. Do not refrigerate.

To Make the Praline Buttercream:
Place the egg whites in the bowl of a electric mixer and beat with the whisk attachment until the whites are foamy and they begin to thicken (just before the soft peak stage). Set the bowl over a saucepan filled with about 2 inches of simmering water, making sure the bowl is not touching the water. Whisk in the sugar 2 tablespoon at a time until the whites are warm (about 120 degrees) and the sugar is dissolved. The mixture should look thick and like whipped marshmallows.

Return bowl to the mixer stand and beat with the whisk attachment on medium-high speed until the mixture is a thick, cool meringue, about 5-7 minutes. Do not overbeat.

With the mixer on medium-low speed, add the butter, a few pieces at a time, beating well after each addition. If the frosting appears to separate or is very liquid after all the butter is added, continue to beat on high speed until it is smooth and creamy. Add the liqueur and vanilla and mix for 30-45 seconds longer, until thick and creamy.

Refrigerate 10-15 minutes before proceeding.

Add 1/3 cup praline paste to the buttercream and whip briefly on medium-low speed to combine. Blend in the rum.

[Buttercream can be refrigerated in an airtight container for up to 5 days or frozen for up to 6 months. If freezing, store in plastic containers and thaw in the refrigerator overnight or at room temperature for several hours.]

To Make the Apricot Glaze:
In a small, heavy saucepan, bring the water and preserves to a slow boil and simmer for 2-3 minutes. If the mixture begins to stick to the bottom of the saucepan, add water as needed. Remove from heat and press the mixture through a mesh strainer, discarding any remnants.

To Make the Ganache Glaze:
Break the chocolate into 1-inch pieces and place in the bowl of a food processor. Pulse until finely chopped and set aside.

In a saucepan, heat the cream and corn syrup on low until the mixture reaches a gentle boil. Carefully pour in the chocolate. After allowing the mixture to sit for 1 minute, slowly stir the chocolate and cream together until the chocolate is melted and incorporated into the cream. Blend in the vanilla and rum or Grand Marnier. If the surface seems oily, add 1/2 - 1 teaspoon hot water. The glaze will thicken, but should still be pourable. If it doesn’t thicken, refrigerate for about 5 minutes. Use immediately.

Assembly:
Divide the cake into 3 layers and place the first layer top side down on a 10" cardboard disk. Using a pastry brush, moisten the layer with 3-4 tablespoons of warm sugar syrup. Spread on a 1/2 inch thick layer of buttercream, leaving a 1/4 inch border around the edge of the cake. Place the middle layer over the first, brush with sugar syrup, and spread with buttercream.

Moisten the cut side of the third layer with additional sugar syrup and place cut side down on the cake. Gently press the sides of the cake to align the layers. Refrigerate for at least 30 minutes before proceeding.

Brush the top and sides of the cake with warm apricot glaze. Chill while you prepare the ganache.

Pour the ganache onto the cake’s center. Move the spatula over the top of the ganache about 4 times to get a smooth and mirror-like appearance. The ganache should cover the top and run down the sides of the cake. When the cake is coated, lift one side of the rack and bang it once on the counter to help spread the ganache evenly and break any air bubbles. (Work fast before the ganache begins to set.) Patch any bare spots on the sides with a smaller spatula, but do not touch the top of the cake after the “bang." Let the cake stand at least 15 minutes to set after glazing.

Leftover cake can be covered and refrigerated for up to 5 days.