Some tips:

1) To make this sponge cake, we can use an electric mixer or a stand mixer; it’s important that the bowl is large because the volume of the whipped egg and sugar mixture will quadruple.

2) The pan (24 cm springform) should be buttered and floured before starting to prepare the cake, to have it ready; the sponge cake batter, in fact, should be poured immediately into the pan and baked quickly, so that the air incorporated in the batter doesn’t escape.

3) Sift together all three powders: rice, chestnut, and potato starch. When we add this mix to the egg and sugar mixture, we will sift it again to aerate it as much as possible and allow it to incorporate as quickly and uniformly as possible.

4) Eggs should be used at room temperature. Take them out of the fridge about half an hour earlier.

5) Preheat the oven to 340°F, static, just before beginning to prepare the sponge cake. It’s essential that the oven has reached the temperature when we bake the sponge cake.

6) The cake’s final decoration made by me is just a suggestion. You can decorate it as you like. In my case, since I had three nice whole boiled chestnuts left over from the filling, I decided to glaze them with chocolate (melted in a bain-marie together with two tablespoons of milk) to put on the cake. This optional step can be done a few hours before decorating the cake, so the chocolate has time to dry.

7) The sponge cake should rest for 6 to 12 hours after being baked. I recommend letting it rest for about 6 hours even after being soaked and filled because it will be much, much better. Of course, it’s just a suggestion; adjust according to your needs.

Let’s prepare the sponge cake

Break the eggs into the chosen bowl, immediately add the sugar, salt, and spices, and whip continuously for 20 minutes (speed 4 if using a stand mixer’s whisk).

As the mixture whips up, it will change color, from yellow (given by the eggs) to an almost “cream white” (like in the photo below).

The success of a good sponge cake lies in the air incorporated by the whipped egg and sugar mixture, which will allow us not to use any leavening agents and give structure and softness to the final product.

After 20 minutes, turn off the whisk and add the flour mix in this way:

-pour a heaping spoonful at a time, passing it through a sieve.

-then, gently plunge the whisk (by hand) into the whipped mass and incorporate the mix with a gentle motion that goes from the bottom (i.e., from the bottom of the bowl) upwards, ideally drawing almost a spiral, repeating this motion two or three times gently, before adding another spoonful.

-continue this way until the mix is finished.

Pour immediately the batter into the pan, gently level with the back of a spoon, and immediately bake on the middle rack. Do not open the oven during the sponge cake’s baking.

During baking, the sponge cake will reach the top edge of the pan and then gradually settle, lowering in height and detaching from the mold’s walls.

At the end of baking, open the oven, do the toothpick test (which should come out dry), and turn off. Leave the oven door slightly open for about ten minutes before removing the cake from the oven.

The sponge cake should be left to cool for about half an hour and then removed from the mold and placed on a cake rack to cool. It should be left to rest for 6 to 12 hours before being cut, soaked, and filled.

Prepare the syrup

Pour the sugar, lemon peel (grated or trimmed but without the internal white part, please) and water in a saucepan.

Put on the heat and bring to a boil. Let the mixture boil for 5 minutes, then turn off and let cool completely (I prepare it the night before or, in any case, a day in advance). The liquor should be added to the cold syrup just before soaking the cake.

Prepare the chestnuts.

In a pot, place whole chestnuts, from which the outer shell has been removed.

Pour water to cover them, add a bay leaf, a pinch of fine salt if you like, cover, and bring to a boil over high heat.

When the water reaches a boil, immediately lower the heat and let the chestnuts simmer for 20 minutes (for large chestnuts like marrons); 12/15 at most for small chestnuts. In my case, it took 20 minutes, as they were large, as you can see from the photo.

After 20 minutes, turn off and leave them in water for another 10 minutes. Then, drain them, let cool for 5 minutes and place them in some room temperature water while peeling, without burning yourself (peel them immediately to avoid it becoming problematic later). Even boiled chestnuts can be prepared well in advance.

After the “rest” period of the sponge cake, we can proceed with cutting, soaking, and filling (also decorating, if we want, which can be done immediately or shortly before serving it, depending on the time we have).

Wash and dry the grapes. Cut the grapes into 4 parts and remove the seeds.

Prepare the cream

Whip the cold cream from the fridge. As soon as the whisk begins to leave visible marks, add the powdered sugar, vanilla paste, and the spreadable cheese, drained of any whey.

Continue to whip for another minute until the cream appears fluffy. For personal taste, the cream is not too sweet, to contrast the sweetness of the filling fruit and the syrup. Taste to see if it is to your liking.

Place the sponge cake already on the serving plate.

Cut it in half, into two discs, with a long and sharp knife or with a cake slicer (very handy, at least for me).

Generously soak the first disc (the one on the plate) with the syrup (the quantity I expected is more than enough, as I prefer to prepare more, but not all of it should be used).

To spread the cream, I preferred to use a piping bag (with the nozzle already inserted because I then had to decorate the surface) to give a uniform height to the cream.

Spread a layer of cream, the same height as the sponge cake disc.

Add the crumbled chestnuts and most of the grapes.

Generously soak the second sponge cake disc and place it on the filling.

The syrup should be abundant but not excessive on sponge cakes, because, in general, the cake is served the next day, and the rest in the fridge tends to dry it out.

Between the two sponge cake discs, embed the remaining grapes (cut) on the outer edge of the filling. (as in the photo below).

Place the remaining cream in a piping bag with a closed star nozzle and decorate, forming roses for the top of the cake. Add more whole grapes and the set-aside chestnuts covered in chocolate (optional step, as described in tip 6).

The sponge cake filled with chestnuts and grapes is ready. All that’s left is to eat it.

The cake should be stored in a cake carrier in a cool place if the temperature permits; otherwise, it should be refrigerated.

Bon appetit