Six-Layer Chocolate Hazelnut Tart by Karla Marro

(This article appeared in the Winter 2021 issue of Pastry Arts Magazine)

The challenge behind creating this dessert was the idea of turning a layer cake into an individual tart. Anchored by a chocolate sablé shell, the layers of the ‘cake’ are composed of chocolate biscuit, hazelnut crisp and chocolate cremeux. A chocolate mirror glaze and candied cacao nibs add a sleek finish to the tart. Make sure to have all the components made before beginning assembly of the dessert.

Yield: 8 individual tarts

Mirror Glaze

• 250 g water
• 665 g granulated sugar
• 475 g heavy cream
• 240 g glucose syrup
• 70 g trimoline syrup
• 180 g cocoa powder
• 30 g gelatin sheets (silver)
• 30 g pure olive oil

1. Boil the water and sugar in a pot.

2. In another pot, boil the cream, glucose syrup and trimoline syrup. Combine the mixtures, along with the cocoa powder, with a hand blender.

3. Soak the gelatin sheet in a bowl of cold water until soft. Remove from the water and squeeze out the excess. Add to the mixture and blend by hand. Add the olive oil. Let the glaze sit for 12 hours before using.

Chocolate Sablé

• 155 g unsalted butter
• 35 g almond flour
• 35 g cocoa powder
• 85 g confectioners’ sugar
• 55 g whole eggs
• 225 g all-purpose flour

1. Place butter, almond flour, cocoa powder and sugar in the bowl of an electric mixer and, using the paddle attachment, whip until creamy. Add the eggs followed by the flour and mix until dough forms.

2. Place the dough between two sheets of parchment paper and roll out to 1/8ʺ thickness, then transfer to the refrigerator and chill until firm, about 30 minutes.

3. Have ready eight 3 1/2ʺ (8.9 cm) sized tart rings. Cut out 10.6ʺ (27 cm) long strips and 2.5ʺ (6.3 cm) circles from the dough. Transfer the cutouts to the refrigerator for 15 minutes.

4. Line the rings with the strips along the sides first and then add the circle at the bottom. Freeze for 20 minutes. Bake for 14 minutes at 330˚F (165˚C), with a rotation every 7 minutes. Allow to cool.

5. Use a microplane to shave the exterior so that they look evenly colored and polished. Set aside.

Chocolate Biscuit

• 160 g whole eggs
• 215 g granulated sugar, divided
• 55 g all-purpose flour
• 60 g almond flour
• 60 g cocoa powder, Valrhona
• 240 g egg whites
• 175 g unsalted butter

1. Whip the eggs in a mixing bowl and add 145 g of the sugar. Whip to ribbon stage.

2. Sift the flour, almond flour and cocoa powder together, then fold into the egg mixture.

3. Whip the egg whites while gradually adding the remaining 70 g of sugar. Fold into batter.  Lastly, add the melted butter. Spread 3/8ʺ (1 cm) thick into a half sheet pan that has been lined with parchment paper or a Silpat mat. Bake at 330˚F (165˚C) for 7 minutes. Cut out sixteen 2.5ʺ (6.3 cm) circles with a round cutter. Set aside.

Hazelnut Crisp

• 100 g Valrhona Jivara 40% milk chocolate
• 220 g hazelnut praline paste
• 200 g pailleté feuilletine

1. Melt the chocolate with the hazelnut paste. Add the feuilletine and place between two silpats.Roll out to 0.12ʺ (3 mm) thick and cut with a 2ʺ (5 cm) round cutter. Keep in the freezer until ready to assemble tart.

Chocolate Cremeux

• 100 g whole milk
• 200 g heavy cream
• 30 g glucose syrup
• 75 g egg yolks
• 125 g Valrhona Tainori 64% dark chocolate

1. Bring the milk, cream and glucose to a boil. Temper the egg yolk mixture in. Over the heat, bring it back up to 180˚F (82˚C) while stirring. Pour over the chocolate and emulsify. Pour mixture into a doser with a plunger. Hold momentarily.

Begin Assembly

1. Line up the tart shells. Add a circle of Chocolate Biscuit. Place Hazelnut Crisp on top.

2. Pour the cremeux over to cover, leaving a small percentage of the rim showing.

3. Fill a slightly smaller ring mold (3ʺ/7.6 cm) with cremeux to height of 0.2ʺ (5 mm). Top with the second Chocolate Biscuit round. Freeze.

Candied Cacao Nibs

• 100 g water
• 100 g granulated sugar
• 100 g cacao nibs

1. Bring water and sugar to a boil. Pour into the cacao nibs. Drain and spread on a Silpat.

2. Bake at 330˚F (165˚C) for 12 minutes. Remove, cool, pack and keep dry and covered.

Final Assembly

1. Unmold the smaller rings (with the cremeux and Chocolate Biscuit). Place them on a glazing rack over a sheet pan and keep them frozen.

2. Melt the glaze in a microwave and bring up to 89˚F (31˚C). Mix with a hand blender. Remove the cremeux from the freezer and glaze them. Place this layer on top of the tart and decorate with the candied cocoa nibs around the exterior.

About Karla Marro

Karla Marro is the Pastry Chef of Acquerello in San Francisco, CA. Her early influence was French pastry chef Pierre Hermé, and her inspiration for creating new recipes is the changing of seasonal ingredients.