Instructions:

Preparing the Sponge Cake

1. Preheat the Oven:
   • Preheat your oven to 350°F (175°C). Grease and line a rectangular baking pan (approximately 9×13 inches) with parchment paper.
2. Prepare the Batter:
   • In a large mixing bowl, beat the egg whites with a pinch of salt until soft peaks form. Gradually add half of the sugar, beating until stiff peaks form.
   • In a separate bowl, beat the egg yolks with the remaining sugar until pale and fluffy. Add the vanilla extract.
   • Gently fold the beaten egg whites into the egg yolk mixture.
   • Sift together the flour and baking powder, then gently fold into the egg mixture, alternating with the milk until just combined.
3. Bake the Cake:
   • Pour the batter into the prepared baking pan, spreading it evenly.
   • Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
   • Allow the cake to cool completely in the pan before cutting it into two equal layers.

Preparing the Custard

4. Make the Custard:
   • In a medium saucepan, heat the milk over medium heat until it begins to simmer.
   • In a bowl, whisk together the egg yolks, sugar, and cornstarch until smooth.
   • Gradually pour the hot milk into the egg mixture, whisking constantly to prevent curdling.
   • Return the mixture to the saucepan and cook over medium heat, stirring constantly, until the custard thickens and coats the back of a spoon.
   • Remove from heat and stir in the vanilla extract and butter. Allow the custard to cool slightly before using.

Assembling the Fruit Pavé

5. Prepare the Fruit:
   • Slice the strawberries, kiwis, mango, and any other desired fruits. Set aside a few slices for garnish.
6. Layer the Pavé:
   • Place one layer of the sponge cake in the bottom of a rectangular serving dish or a trifle dish.
   • Brush the cake layer with orange juice to moisten it.
   • Spread a generous layer of custard over the cake, followed by a layer of mixed fruit slices.
   • Repeat the layers with the second sponge cake layer, brushing with orange juice, spreading custard, and topping with fruits.
7. Final Touches:
   • Garnish the top layer with the reserved fruit slices, arranging them in an attractive pattern.
   • Chill the assembled pavé in the refrigerator for at least 2 hours, or overnight, to allow the flavors to meld.

Serving

8. Garnish and Serve:
   • Before serving, add a dollop of whipped cream and fresh mint leaves on top for an extra touch of elegance.
   • Slice the pavé into squares and serve chilled.