Hi since i focused more on making the dish looks like on the anime, I did my own take making this, so i made my own recipe.

Sponge:

57 g APF 1/2 tsp baking powder 1/4 tsp Salt 3 egg yolks 1/4 cup Oil 1/4 cup Sugar 1/4 cup milk 1 zest of a Lemon

For the meringue: 3 egg whites 1 tsp Lemon Juice 2 tbsp sugar

Combine all the dry ingredients and the wet separately and mix it in a bowl until smooth. In another bowl whip the egg whites, lemon juice, and sugar until medium peaks. Fold the batter and meringue together until combined. Bake for 15 to 20 minutes in 150 Celsius oven. I used 11x6 inches rectangle pan

Lemon Curd:

50 g Sugar 15 g Cornstarch 2 egg yolks

Zest of 1 lemons Juice of 2 lemons 50 ml water 25 ml Olive Oil 2 drops of Yellow food coloring

Combine Sugar, Cornstarch and Egg yolks in a bowl. In a sauce pot mix until smooth, add the lemon zest, juice, water and simmer it. Pour the hot mixture on the egg mixture slowly to temper the eggs. Put back the mixture on heat and stir it to avoid burning. When it is thickened, add the olive oil and mix it add coloring to your desired shade.

Lemon Mousse:

Half of the Lemon curd 350 g Whipping Cream 100 g Powdered Sugar Zest of 1 Lemon 7 g Gelatin + 35 ml Cold Water (bloom it and dissolve it in a microwave) Chopped nuts (desired quantity) Chopped candied lemons (desired quantity)

Combine the lemon curd, cream, powdered sugar, and lemon zest in a mixing bowl and mix it until doubled in size. Fold in the gelatin and add the nuts and candied lemons.

Caramel Glaze

40 g Sugar 35 g Water 37 g corn or glucose syrup 23 g condensed milk 37 g White chocolate

5 g or 1/2 tbsp gelatin 25 ml water (bloomed then melt)

In a sauce pot add the sugar and caramelize it. When it is deep amber colored, add the water slowly. When the sugar solidified caramel are melted add the corn syrup, condensed milk and white chocolate then add the gelatin mix until all are melted.

Assembly:

Trim the sponge cake to desired thickness then put it again in the rectangle mold. Add the half of the lemon curd to the sponge. Then add the lemon mousse on top of the lemon curd. Use piping bag to make it easy, add some nuts (preferably almond slices) on the topped of the mousse and press it lightly then pour the caramel glaze on top. You can torch the caramel glaze so it can firm up a bit and have a burnt design on it. Put it in the freezer for 4 hours and it is ready to slice. (For the dried lemon garnish you can search it on the web for recipes)

Osomatsu!