01 - Preheat oven to 350°F (180°C). Grease two 8-inch round cake pans and line with parchment paper.
02 - In a large mixing bowl, beat eggs, granulated sugar, and salt with an electric mixer on high speed for 5 to 7 minutes, until thick, pale, and tripled in volume.
03 - Gently fold in all-purpose flour and vanilla extract using a spatula, taking care not to deflate the mixture.
04 - Divide batter evenly between prepared pans and bake for 20 to 25 minutes, until cakes are golden and resilient when pressed.
05 - Let cakes cool in pans for 10 minutes. Turn out onto a wire rack and cool completely.
06 - In a mixing bowl, whip heavy cream, powdered sugar, and vanilla extract together until soft peaks form.
07 - Optional: Spread a thin layer of strawberry jam over one cooled sponge. Top with half the whipped cream and arrange half of the sliced strawberries over cream.
08 - Set second sponge on top. Spread remaining whipped cream over and decorate with remaining strawberries.
09 - Garnish with fresh mint leaves if desired. Chill cake for at least 30 minutes before slicing.