As the lilac trees begin to bloom, it seems to be the perfect time to make one of summer’s most beautiful cakes – a rhubarb lemon mousse cake all the way from Finland.

Hanna Amy who lives in Finland shares this most delicious recipe for a cake that seems to captures all the wonderful essence of summer that we all love and want to hold on for as long as possible. With berries, rhubarb and the tangy taste of lemon, you can feel summer in every bite.From Hanna,

After the apple trees have blossomed, lilacs begin to bloom letting out their magnificent fragrance linger the air, which symbolizes the middle of summer. Additionally, the first harvest of rhubarbs is ready to be eaten and that calls for a sweet jam and therefore summer’s first layer cake. Baking has increased in popularity during covid-19, probably because it is therapeutic and quite fulfilling in some retrospect. Pinterest worthy semi-naked cakes have slowly become more common in Finland, as today the visual aspect is just as important as the taste of the cake. This cake is a real statement dessert and therefore it is a great staple and impressive recipe to have in your kitchen. Now we can set our flower crowns down from midsummer, put our aprons on and focus on what makes life sweet.The whole of Finland is experiencing the most incredible heat waves, the sun has kissed our faces and bleached the hair and people are starting to smile and embrace the short-lived season. July brings a number of small gatherings like garden parties, occasional birthdays and get togethers, hence I wanted to share this rhubarb and lemon butter cream semi-naked cake with subtle flavors of cardamom in the layers. Cardamom and cinnamon  are possibly the most used spices in Scandinavia, no surprise as they are hearty and earthy with heaps of depth. I made the cake the day before a party, and I love how overnight the texture of the cake merges becoming more dense and juicy, making it extra delicious the following day. The sweet cinnamon rhubarb jam marries well with the refreshing lemon mousse all tucked between creamy walls of butter frosting.Before getting started, do not let this recipe overwhelm you. It looks long because it has a few parts to it, but once you get the hang of it, making the cake becomes a quick tradition. Begin by making the rhubarb jam, lemon curd & lemon mousse for the cake. The great thing is that all three can be made well in advance, leaving less work on the actual day when assembling the cake.

Rhubarb Jam Recipe

• 4 large rhubarb stems, chopped
• 1 cup sugar
• 1 tablespoon cinnamon
• about 1 cup water

Directions:

In a saucepan, boil 1 cup of water. Add the chopped rhubarb into the water along with the sugar and cinnamon and let it boil for about half an hour. Stir occasionally and once the rhubarb is totally soft and mushy, the jam is ready. Let the jam cool and place into the fridge.

Lemon Mousse Recipe

• 1/2 cup lemon curd (can use store bought too)
• 1 cup cold heavy whipping cream
• 1/4 cup powdered sugar

Directions:

For the lemon mousse, you basically mix 3 ingredients together; lemon curd, whipped cream and powdered sugar. You could buy the curd in a store but if you want to make it yourself, see the recipe below.

To make the Mousse: In a bowl, whisk the whipped cream and powdered sugar. Whisk in the lemon curd for about 3 minutes until soft peaks start to form. Place into a clean bowl, cover with cling film and refrigerate overnight.

Lemon Curd Recipe

• 2 eggs room temperature
• 1 egg yolk (optional)
• 100 dl sugar
• Juice of 1 lemon
• zest of 1 lemon
• 50g-70g butter, roughly cubed (room temperature)

Directions:

In a saucepan, add in all the ingredients and gentle stir over love heat for about 10-15 minutes with a whisk. The sauce will begin to thicken slowly and once thickened, pour into a jar to cool. This can be done the night before so the flavours really intensify and the mixture becomes more stiff.

Now that all the fillings are made, it is time to make the frosting and cake bases:

Cake Frosting Recipe

• 500g sifted icing sugar
• 250g butter
• 1-2 tablespoons boiling water

Directions:

To make the butter cream, beat together butter (room temperature) and icing sugar on low speed with a hand held mixer. Add a few drops of boiling water to loosen the butter so it forms a lovely frosting as you mix.

Cake Recipe

• 3 eggs
• 1dl sugar
• 1/2 teaspoon baking powder
• 1 dl + 1 1/2 tbsp flour
• 1 tablespoon cardamom
• ½ tablespoon lemon zest
• * oil for lining the cake tine / milk when assembling the cake

Directions:

Baking the cake layers:

In a bowl, add together the dry ingredients (minus sugar & lemon zest). In another bowl, whisk together the eggs and sugar until light and fluffy with the help of an electric whisk. Through a sieve, combine the dry ingredients to the egg/sugar mixture. Gently fold the batter together and add the lemon zest.

Pour some oil into the cake tin so the bottom and sides are coated, pour excess out. Pour batter into the cake tin and place into the bottom part of the oven for 40 minutes at 175 °C. Check the cake by inserting a toothpick into the centre and if it comes out clear, it is fully cooked. Cool in cake tins on a heat rack (about 10 minutes); remove cakes from tins and cool completely on wire racks for about an hour.

Repeat this process once more for another layer.

Freeze Cake layers:

Freeze cakes once cooled, as this process makes the assembling much easier. Wrap each cake layer individually in plastic wrap and freeze for 4 hours. This part is optional but it ensures that crumbs don’t break into the icing, so if you are short in time, freeze at least for an hour. If you freeze them overnight, give them a bit of time to defrost as they are hard to cut otherwise.

When you are ready to assemble the cake, remove layers from freezer and unwrap. Level the layers with a serrated knife to make sure the surfaces are straight. I removed the top half of the cake layers as they were dome-shaped. I also cut one of the layers in half, to get an extra layer for the center of the cake.

Assemble the cake:

At this point, remove the lemon mousse and jam from the fridge and have butter frosting ready.

Use one of cakes for the base layer of the naked-cake. Save the prettiest bottom for the top part. Place a bit of frosting on your cake plate and place the first layer on top. This keeps it from moving. Moisten each layer with a bit of milk.

Fill each layer with rhubarb jam and lemon mousse. Repeat this process until the top and place the last layer “with the bottom half of the layer facing the surface” so it looks flat this way. Add buttercream frosting around the edges of the cake and push it in the middle to fill any gaps and scrape to almost bare with a sharp knife. Place into fridge to set the frosting before decorating. Decorate with black berries, mint leaves and dried rose buds, that you would use for tea.Now that summer is in full swing, collect some wild flowers, make yourself a cup of tea and allow the sweet flavors of this cake to take over your palette. Beautiful cakes like this make you live in the moment and embrace the joy in the ordinary.

{Photo and Words by Hanna Kirstiina Amy, Website: www.xoamys.com, Instagram: @xoamysnordic }

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