When I saw Le Gâteau Vert-Vert at the Great British Bake Off, I wanted to try it. As a child, my favourite cake was Krantz cake, a German cake my grandmother used to make for me for my birthday each year. That cake has walnuts in both the sponge and cream. My husband loves cakes and desserts with nuts too, so he was very happy for me to try this cake.

Le Gâteau Vert-Vert has a lovely story. It was made by Claude Monet’s wife and it was his favourite cake. I loved the story behind it and I thought I’m going to love the cake too. So, I started by doing a bit of research. On the French websites that I looked, all had fondant instead of pistachio marzipan. I have to admit I was surprised to see so much sugar in an authentic French recipe. Finally I found an website where three ladies made a podcast, in French, with details about the cake and a few personal details about Monet. It was fascinating to listen to the description of Monet’s kitchen, in a lovely blue and white colour scheme. They had the original recipe made by his wife. While listening was not complicated at all, taking notes in English at the same time, considering that neither of those are my first languages was a bit of a challenge. The recipe is with fondant, that part was clear.

In the end, I’ve decided to make it with pistachio marzipan because that was one of the thing that most appealed to me in this cake. By the way, if you saw that episode, one of the participants asked who makes their marzipan at home. I was puzzled, I imagine anybody who wants to appear at Bake Off would make their marzipan at home, especially as the shop bought one is only made with almonds and, of course, the ratio sugar to almonds is 2 to 1. At home I make my marzipan to the ration 2 to 1 almonds to sugar, more taste, less sugar. A few years ago Mary was surprised that a contestant didn’t make his own fondant while all the rest did, and fondant is only sugar, the standards seem to have slipped a bit.

I loved this cake. It has a lovely flavour of pistachios and the textures from the sponge, cream, and the pistachio marzipan on top are fantastic. I will make this cake again, that is certain. Although next time I’m going to use a bit of green food colouring instead of going to all that trouble with the spinach juice.

Ingredients for Le Gâteau Vert-Vert:

Joconde sponge:
– 4 eggs
– 25g butter
– 75g sugar
– 75g flour
– 50g pistachios
– 4 tsp Kirsch – for soaking the cake
pistachio creme:
– 2 eggs and 2 yolks
– 100g butter, at room temperature
– 200ml milk
– 100g pistachios
– 100g icing sugar
– 2 tsp of Kirsch
– 2 tsp white plain flour
pistachio marzipan:
175g pistachio kernels
90g icing sugar
1 tsp pistachio flavouring
2 spoons water
green icing and decoration:
icing sugar
spinach
water
edible flowers. I’ve used Borage flowers
30g pistachios

Start by making the sponge. Heat the oven at 180C or 160C fan.

While the oven is getting ready, make the sponge batter. In a bowl whisk the egg whites, add half of the sugar and continue until they form firm peaks. In a bigger bowl, mix the yolks with the rest of the sugar until pale. Now add the flour, grounded pistachios, and the butter, and mix. Fold in the beaten egg whites. Pour the cake batter in an oiled baking tray. Put the sponge in the oven and let it bake for 35 to 40 min. Mine took 40 minutes to bake.
When the sponge is baked, take it out of the oven, leave to cool for a couple of minutes, then transfer it to a cooling rack and let it cool completely.

While the sponge is in the oven, you can make the pistachio cream. It will need to cool down. Blitz the pistachio kernels until they are grounded, but keep them a bit coarse. In a bowl, mix the pistachios with the butter until it forms a pistachio butter. Meanwhile, in a pan, heat the milk. In a bowl, whisk the eggs and the yolks with the sugar. Add the flour, the Kirsch, and whisk again. When the milk has boiled, pour it over the egg mixture. Mix for one minute or so. Pour the mixture back into the pan and keep it over medium heat. Stir continuously for 2-3 minutes. Take it off the heat and continue to stir until it cools down. You can put the pan in a bowl with iced water to speed up the process. When the cream is cool, tip the pistachio butter on top and incorporate. Now you can place the bowl in the fridge to cool down completely.

In a sauce pan, put the spinach leaves and 120ml water. Leave to boil for 2 minutes. Then put the spinach in a blender and blitz. Pass the spinach through a sieve and keep the juice for making the icing. Instead you can use a bit of food colouring that does the same job.

Assemble the cake. Cut the sponge in three even layers. Brush Kirsch on top of the first layer. Keep a couple of spoonfuls of cream. Divide the rest of the cream into two and spread the first cream on the first layer. Place the second layer of sponge on top, brush it with the remaining Kirsch, and spread the rest of the cream. Put the last layer on top. Using a knife, spread a thin layer of cream all over the cake. This will ensure the pistachio marzipan will adhere to the cake. Keep the cake in the fridge until you are ready to put the marzipan on it.

Make the pistachio marzipan by grounding the pistachios in a food processor. If you leave them coarse it will be a bit more difficult to work with, but it will add a different texture to the cake. Simply put the pistachios and the icing sugar in a bowl, add the pistachio flavouring and a couple of spoons of water. Mix with a spoon. Then tip it on the worktop and make the marzipan by kneading the ingredients in. Add more water, a teaspoon at a time, until it has the right consistency. The whole process should take about 2 minutes at the most.

Sprinkle icing sugar on the worktop and roll out the marzipan. Make sure the worktop and the rolling pin are covered with icing sugar. I’ve used the 4mm setting for the rolling pin and it is the perfect size. When the marzipan is rolled, you can take the cake out of the fridge and cover it with the marzipan. Remove the excess and make some balls with it. They will look lovely on the cake.

Now make the green icing. In a bowl, mix icing sugar with spinach juice until you have a thick icing, enough to cover the cake. I’ve used over 250g of icing sugar for this, but at least half of it ended up on the worktop. I wanted to have a thin layer, so my icing was on the runny side. If you prefer a thick layer of icing, then make it thicker and use a bit more icing sugar. Transfer the cake from the cooling rack to the serving plate. I didn’t realize mine wasn’t centered, but didn’t want to risk moving it.

Cut the pistachios for the decorating. Put most of them on the plate, around the cake, then gently push them into the cake. Sprinkle the rest on top, in the middle of the cake. Place the pistachio marzipan balls and the edible flowers. Now the cake is ready to be enjoyed.

After making this cake I know I’m going to make it again, exactly like this. The only thing I’m going to chance is the colouring of the icing sugar, when I’m going to use modern-day food colouring, that was not available at the time this cake was made.

Part of Bake Off Bake Along.