Green Tea Opera Recipe

Prepare oven and pan

Preheat oven to 180°C (350°F). Line a 10x15 inch (or similar) rimmed baking sheet with parchment and lightly grease.

Whisk eggs and sugar

In a heatproof bowl set over barely simmering water (double boiler), whisk the 4 eggs and 100 g sugar until warm to the touch (~40°C / 104°F) and sugar is dissolved, about 3–4 minutes.

Whip to ribbon stage

Transfer the warm egg mixture to a stand mixer fitted with the whisk (or use a hand mixer). Whip on medium-high until pale, thick, and ribbon-like when the whisk is lifted (about 6–8 minutes).

Fold dry ingredients

Sift together the 70 g cake flour, 4 g matcha powder, and pinch of salt. Gently fold the dry mix into the whipped eggs in three additions, using a rubber spatula and cutting motions to preserve volume.

Incorporate butter

Temper the 30 g melted butter by whisking a large spoonful of batter into the butter, then fold that back into the batter until just combined. Add 1 tsp vanilla. Do not overmix.

Bake

Spread batter evenly in the prepared pan to about 1 cm thickness. Bake 10–12 minutes until the surface springs back and a toothpick comes out clean. Immediately invert onto a clean kitchen towel, peel off parchment, and roll or keep flat to cool. Trim into strips or layers once cooled (approx. three 10x5 cm layers).

Beat butter

In a bowl, beat the 200 g softened butter until pale and creamy, about 3–4 minutes.

Add sugar and matcha

Gradually add 180 g sifted confectioners' sugar, about 1/3 at a time, beating on low until incorporated. Sift in 6 g matcha powder to avoid lumps and add a pinch of salt.

Adjust texture and flavor

Add 1 tsp vanilla and 2 tbsp cold cream. Beat on medium-high 2–3 minutes until light and fluffy. Taste and adjust matcha or sweetness as needed. Keep at room temperature until assembly (if warm kitchen, refrigerate briefly then rewhip).

Heat cream

Place 120 ml heavy cream in a small saucepan and heat until just simmering (do not boil).

Make ganache

Pour hot cream over 150 g chopped dark chocolate in a heatproof bowl. Let sit 2 minutes, then whisk gently from center outward until smooth and glossy. Whisk in 15 g cold diced butter for shine. Let cool until spreadable but still pourable (room temperature).

Combine anko and cream cheese

In a bowl, beat together 200 g sweetened azuki bean paste and 100 g softened cream cheese until smooth and homogenous.

Lighten with cream

Slowly add 60 ml cold heavy cream while continuing to beat until lightened to a spreadable mousse consistency. Stir in 1 tsp vanilla. Chill briefly if too soft before assembly.

Prepare batter

Preheat oven to 160°C (320°F). In a bowl combine 60 g toasted ground hazelnuts, 40 g all-purpose flour, 40 g confectioners' sugar, and a pinch of salt. Stir in 40 g melted butter and 1 egg white to form a smooth, slightly runny batter.

Bake thin wafers

Drop tablespoons of batter onto a silicone mat or parchment spaced well apart and spread thinly into rounds (or bake as a single thin sheet then cut). Bake 8–10 minutes until edges are golden. Remove and shape quickly if desired (curl over a rolling pin) or let cool flat to keep as crisp wafers. Make enough to fit between layers and for garnish (about 8–10 small wafers).

Make matcha base

Whisk together 200 ml whole milk, 200 ml heavy cream, 60 g sugar, 6 g sifted matcha powder, and a pinch of salt until sugar and matcha are fully dissolved and no lumps remain. Chill mixture thoroughly, at least 2 hours or overnight.

Churn or no-machine method

If you have an ice cream maker: churn according to manufacturer's instructions until soft-serve consistency, then freeze until firm (2–4 hours). If no machine: pour chilled mixture into a shallow metal pan, freeze 30–40 minutes until edges firm, whisk vigorously to break crystals, repeat 3–4 times until smooth and frozen, then transfer to container and freeze until firm.

Trim génoise

Trim the cooled green tea génoise into even rectangular strips to form layers (suggested: 3 layers about 10x5 cm each). Keep any scraps for serving or crumbs.

Layering

Place first génoise layer on a board. Spread an even layer (about 30–35 g) of matcha buttercream. Place second génoise layer, spread about 30 g azuki bean cream, then a thin hazelnut wafer. Place third génoise layer and press gently. Top with a thin layer (10–15 g) of matcha buttercream to level.

Ganache finish

Spoon cooled but pourable dark chocolate ganache over the top, spreading to cover the top and allowing a small amount to drip down the sides for an opera-style glaze. Chill 20–30 minutes to set.

Decorate and serve

Pipe or dollop small rosettes of matcha buttercream and azuki cream on top or along the sides. Insert hazelnut wafers as crisp accents. Serve slices with a scoop of matcha ice cream on the side. Keep refrigerated; remove from fridge 10 minutes before serving to soften slightly.