Naked cake hazelnut, grapefruit & strawberry

I rarely use grapefruit in baking, because as much as I love it, I'm not the only one eating my cakes and the people around me don't like it very much. This cake is an exception, made for my birthday. I combined three of my favourite flavours, hazelnut, strawberry and grapefruit. It's a cake that's easy to make and assemble, and requires little equipment apart from the baking tin. Of course, if you don't like grapefruit, you can very well replace it with lemon (lemon, hazelnut and strawberry works very well too)!



Prep time : 50 minutes + 30 minutes cooking
For a cake 12cm in diameter and about 20cm high :

Grapefruit crème pâtissière :

90g sugar
3 eggs
50g butter
165g grapefruit juice
20g cornstarch

Whisk the eggs with the sugar and cornstarch.



Heat the grapefruit juice and pour it over the eggs, still whisking.




Pour back into saucepan, and thicken over medium heat, stirring constantly.



Off the heat, add the butter cut into small pieces (if necessary, use a hand blender to homogenize the texture).



Put a plastic wrap on it and let it cool. Meanwhile prepare the hazelnut cake, and only prepare the diplomate cream when you are ready to assemble.

Hazelnut cake :

3 eggs
75g melted butter
70g brown sugar
55g hazelnut praliné
90g flour
75g hazelnut powder
75g milk
5g baking powder
1 pinch of salt

Whisk the eggs with the sugar and praliné. Add the melted butter, the salt, then the sifted powders (flour, baking powder, hazelnut powder).




Finish by adding the milk.



When the dough is homogeneous, pour it into a buttered and floured or sugared 12cm diameter mould.




Be careful, your pan must be high enough, otherwise do as I did and bake the dough in two times.
Bake it in the preheated oven at 180°C for about 30 minutes (check the baking with the tip of a knife, it should come out dry).

Grapefruit diplomat cream :

Grapefruit crème pâtissière
165g liquide cream 30 or 35% fat

When the cake is baked and cooled, and the crème pâtissière cold, whip the liquid cream into a whipped cream.



Add a spoonful of whipped cream to the cream, stirring vigorously.



Add the rest gently with a maryse, then proceed with the assembly.

Assembly :

400g strawberries

Cut the strawberries into small cubes.
Cut the cake into "slices" in the thickness, then put the diplomat cream in a piping bag.




Start by piping the cream around the edge of the cake, then a little cream in the middle and garnish with diced strawberries.



Cover with another slice of cake, and continue this way until the end.



For the decoration, I simply piped a little diplomat cream with a Saint-Honoré tip, then put on the cake some hazelnuts and strawberries.
Enjoy !