Fruit Filling for Sponge Cake

Ingredients

• 6 sheets of white gelatin
• 500 g fruit (as desired, e.g., berries or stone fruits)
• 2 Eggs
• 1 Egg white
• 50 g powdered sugar (4 tbsp)
• 125 ml cooking cream (15% fat; very well chilled)
• 1 small organic lemon
• liquid sweetener (optional)

Instructions

1. 1.

   Soak gelatin in plenty of cold water for 10 minutes. In the meantime, wash, peel if necessary, and pit the fruit, then place it in a tall container.

2. 2.

   Puree the fruit with an immersion blender until fine; strain through a fine sieve if desired to remove seeds. Weigh out 250 g of the fruit puree.

3. 3.

   Separate the eggs. Whisk 2 yolks with 1 tbsp cold water and powdered sugar in a bowl (use remaining yolk elsewhere). Beat with a hand mixer’s beaters into a thick, almost white cream. Fold in the fruit puree briefly.

4. 4.

   Drain the gelatin and place it in a saucepan. Gently melt under low heat while stirring.

5. 5.

   First whisk 1–2 tbsp of the egg‑fruit mixture into the warm gelatin, then fold this into the remaining egg‑fruit cream; this prevents the gelatin from curdling.

6. 6.

   Cover the cream and refrigerate for about 15 minutes until it begins to set. Test with a spoon: if the trail remains flat, the consistency is perfect.

7. 7.

   While the cream sets, beat the very chilled cooking cream in a bowl with a hand mixer’s beaters until light and creamy (it won’t be as stiff as whipped cream).

8. 8.

   Rinse the lemon hot, dry it, then pierce its peel 2–3 times with a long wooden skewer and squeeze out ½ tsp of juice into a tall bowl.

9. 9.

   Add the egg whites and beat with a hand mixer’s beaters until stiff peaks form.

10. 10.

    Fold the meringue and beaten cooking cream into the lightly set fruit cream using a rubber spatula. Whisk in, repeatedly pulling through all layers but avoid stirring. Sweeten to taste if desired. Use immediately to fill sponge cake bases or mini cakes; if left too long, the filling becomes too firm for spreading.