How to make strawberry mousse cake step by step

Step 1 - preparations

• Line the baking pan with parchment paper or grease it with butter and dust with flour.
  
• Preheat the oven to 180℃ in top/bottom heating mode.

Step 2 - preparing strawberry puree

• Wash the strawberries, remove the stems, and cut the fruit into smaller pieces.
  approx. 350 g strawberries
• Mix or blend the fruit thoroughly.
  
• Strain the strawberries through a fine-mesh sieve - I strained them directly into a saucepan.
  
• Add sugar to the strawberries, mix, and heat the mixture until the sugar dissolves and the excess juice slightly evaporates.
  100 g sugar
  
• Cover the gelatin with a little cold water and set aside for a moment to swell.
  1-2 teaspoons gelatin
  
• Add the swollen gelatin to the hot strawberries, mix, and set aside to cool completely.
  

Step 3 - preparing the creamed batter

• Sift the flour together with the baking powder through a sieve.
  300 g all-purpose flour, 2 teaspoons baking powder
  
• Place butter, oil, sugar, and vanilla in a large bowl.
  140 g butter, 3 tablespoons oil, 200 g sugar, vanilla extract
  
• Mix them together on high speed until you get a fluffy, light mixture.
• Add one egg at a time - mix each briefly - just until combined.
  3 eggs
  
• Add about half of the sifted flour and mix briefly on low speed.
  
• Add natural yogurt and mix briefly.
  300 ml plain yogurt
  
• Add the rest of the flour and mix briefly - just until combined - stop mixing when you can still see remnants of flour - then fold in the batter with a spoon.
  
• Transfer the batter to the prepared pan.
  

Step 4 - baking the cake

• Place the pan with the batter into the preheated oven and bake for about 35-40 minutes - until a wooden skewer comes out clean.
• After baking, cool the cake completely.

Step 5 - preparing the strawberry mousse

• Pour the cold heavy cream into a bowl and whip on high speed until you get very thick whipped cream.
  300 ml heavy cream
  
• Add the cooled strawberry puree to the cream and gently mix with a spoon.
  
• Spread the mousse over the cooled cake and smooth the surface.
  
• Refrigerate the cake for at least 2 hours - so that the mousse sets.