Petit Green Tea Opera Recipe

Prepare and Whip

Preheat oven to 180°C (350°F). Line a 23x33cm (9x13in) sheet pan with parchment. In a heatproof bowl set over barely simmering water, whisk together eggs and granulated sugar until warm (around 40–45°C). Remove from heat and, using a stand or electric mixer, whip the eggs and sugar on high until thick, pale, and ribbon-like (about 6–8 minutes).

Fold Dry Ingredients

Sift cake flour and matcha together. Fold about one-third of the whipped egg mixture into the dry ingredients to loosen, then gently fold the remainder until just combined. Avoid deflating the batter.

Incorporate Butter

Temper the melted butter by whisking a tablespoon of batter into the butter, then fold the butter mixture back gently into the batter along with vanilla and a pinch of salt until homogeneous but light.

Bake

Spread batter evenly in prepared sheet pan. Bake for 10–12 minutes, or until the top springs back lightly and a skewer comes out clean. Immediately invert onto a cooling rack or clean towel, peel off parchment, and allow to cool fully. Trim into rectangles appropriate for petit opera layers (recommend 3–4cm x 8–9cm strips), or use round/rectangles as desired.

Cream Butter

Beat room-temperature butter on medium speed until smooth and pale (about 2–3 minutes).

Add Sugar and Matcha

Gradually add sifted powdered sugar and continue beating until incorporated. Add sifted matcha, vanilla, salt, and milk. Beat on medium-high until light, fluffy, and spreadable (2–3 minutes). Adjust consistency with a teaspoon of milk if too stiff.

Make Ganache

Place chopped dark chocolate in a heatproof bowl. Heat heavy cream until it just begins to simmer, then pour over the chocolate. Let sit 1–2 minutes, then whisk gently from center outward until smooth and glossy. Stir in butter if using for extra shine. Cool to a thick but pourable/spreadable consistency before assembling (about 20–30 minutes at room temperature or brief chill).

Make Azuki Cream

If using prepared anko (sweet red bean paste), place it in a bowl. Whip the heavy cream with powdered sugar until soft peaks form. Fold the whipped cream into the anko gently until homogenous but still slightly airy. Taste and add a pinch of salt to balance sweetness. Chill until assembly to maintain structure.

Prepare Dough

Preheat oven to 170°C (340°F). Beat softened butter with powdered sugar until creamy. Add egg white and mix until smooth. Fold in ground hazelnuts, flour, and salt until a soft dough forms.

Shape and Bake

Roll dough thin between parchment to about 2–3mm thickness or pipe small rounds/rectangles for wafers. Place on lined baking sheet and bake 8–10 minutes until edges are golden. Remove and cool completely — wafers should be crisp. If needed, trim to size matching cake layers.

Infuse Matcha & Temper

Whisk matcha with a small amount of milk to make a smooth slurry (no lumps). In a saucepan, heat remaining milk and cream with sugar to just below simmering. Whisk a few tablespoons of hot milk into the matcha slurry to warm, then return that mixture to the pan and whisk to combine.

Make Custard

Whisk egg yolks in a bowl. Temper yolks by slowly whisking in about 1/3 of the hot matcha milk, then return the yolk mixture to the saucepan. Cook over medium-low heat, stirring constantly with a spatula, until the custard coats the back of a spoon (about 78–80°C) — do not boil.

Chill and Churn

Strain custard through a fine sieve to remove any bits and ensure smoothness. Cool quickly in an ice bath, then refrigerate until fully cold (at least 3 hours or overnight). Churn in an ice cream maker according to manufacturer directions until soft-serve consistency, then transfer to a container and freeze at least 2 hours to firm.

Trim Layers

Trim the cooled génoise into uniform rectangles for petit portions (recommend 4 to 6 layers per petit opera: two sponge layers, two buttercream layers, a ganache layer and azuki layer depending on desired structure). Lightly brush sponge pieces with simple syrup if you prefer added moistness.

Layering

On a clean board, place first sponge strip. Pipe or spread a thin even layer (about 6–8 g) of matcha buttercream. Place a second sponge layer, then spread a thin layer of azuki bean cream (about 8–10 g). Next, place another sponge, spread a thin layer of ganache (cool but spreadable) about 7–10 g. Repeat if making additional tiers, finishing with a top layer of sponge.

Finish Top

For the top, pour or spread a thin glossy layer of ganache and chill briefly to set. Pipe a small rosette of matcha buttercream and a small quenelle or dot of azuki cream for contrast. Insert a piece of hazelnut wafer on the side or on top for crunch and garnish with a light dusting of matcha or cocoa.

Serve with Matcha Ice Cream

Plate one petit opera with a small scoop (30–40 g) of the chilled matcha ice cream. Serve immediately so the ice cream remains firm yet scoopable.

Storage

Store assembled petits in an airtight container in the refrigerator up to 2 days. The hazelnut wafer may soften; store wafers separately and add at service if possible. Matcha ice cream should be kept frozen until serving.