Make the Matcha Nama Chocolate Filling

1. Prepare the tray: Line a 15 x 15 cm baking tray with parchment paper.
2. Make a matcha paste: In a small bowl, mix matcha powder with a few teaspoons of heavy cream until a smooth paste forms. Gradually add 1–2 more tablespoons of cream, mixing well.
3. Melt the chocolate: In a heatproof bowl, combine the chopped white chocolate and remaining heavy cream. Microwave at 600W in 30-second intervals, stirring after each, until fully melted and smooth (about 6 rounds).
4. Combine: Add the matcha paste to the melted chocolate mixture and mix with a rubber spatula. It may look separated at first—keep stirring until it becomes smooth and shiny.
5. Finish the ganache: Whisk in the butter until fully incorporated. Pour the mixture into the prepared tray, smooth out the surface, and chill until firm (about 1–2 hours in the fridge).

Make the Matcha Cookies

1. Cream the butter & sugar: In a stand mixer, beat softened butter until smooth. Add powdered sugar and mix until light and creamy.
2. Add the egg yolk: Mix in the egg yolk until fully incorporated (it may look slightly separated, which is normal).
3. Incorporate the dry ingredients: Sift in the matcha powder, almond flour, and cake flour. Mix on low speed until a smooth dough forms.

Roll & Chill the Dough

Option 1: Using Ziplock Bags

• Divide the dough into two portions. Place each portion inside a ziplock bag and roll out evenly to a thin sheet.

Option 2: Using Pastry Rulers

• Divide the dough in half. Place each portion between two sheets of parchment paper and roll out to 3–5mm thickness, forming a 15 x 15 cm square.
• Transfer the rolled-out dough to a flat surface and refrigerate for 30–60 minutes until firm.

Cut & Bake the Cookies

1. Preheat the oven to 160°C (325°F).
2. Cut into squares: Using a sharp knife or cookie cutter, cut each chilled dough sheet into 9 squares (5 x 5 cm).
3. Bake: Arrange on a parchment-lined baking tray and bake for 18–22 minutes (20 minutes is ideal for most ovens) until the edges are set but not browned.
4. Cool completely before assembling.

Assemble the Sandwich Cookies

1. Cut the ganache: Heat a knife in boiling water, wipe it dry, and cut the chilled ganache into 9 squares (5 x 5 cm). Clean the knife between cuts for sharp edges.
2. Sandwich the cookies: Place a ganache square onto the flat side of a cookie. Top with another cookie and gently press to adhere.
3. Optional: Seal with tempered chocolate – Brush the inside of each cookie with tempered white or dark chocolate to keep them crisp.
4. Chill before serving: Refrigerate the sandwiches for at least 30 minutes to allow the flavors to meld.