Cut the castella bread into 1cm thick slices and use a 6cm round cookie cutter to shape them.

Place the cut castella bread at the bottom of the mold and wrap with mousse rings.

Soak gelatin sheets in ice water one by one, remove excess water, and melt with 1 tbsp of heavy cream using a double boiler.

Whip 150g of heavy cream with sugar until it reaches 70% stiffness.

Mix the melted gelatin into the yogurt, then fold in the whipped cream.

Pour the yogurt mousse into the mold, filling it up to 70%, and refrigerate for at least 1 hour to set.

For the jelly, soak gelatin sheets in ice water and prepare the green grape juice by warming it in the microwave for 30–40 seconds.

Remove excess water from the soaked gelatin and mix it into the warmed green grape juice. Let it cool slightly.

Place green grapes and blueberries on top of the set yogurt mousse, then pour the green grape jelly mixture over them.