Preheat oven to 340°F (170°C). Line an 8-inch round cake pan with parchment paper. In a large bowl, beat eggs and sugar using an electric mixer until pale, thick, and tripled in volume (about 8-10 minutes). Gently fold in sifted flour in three additions using a spatula. Add melted butter and vanilla, folding gently until just combined. Pour into prepared pan and bake for 25-30 minutes until golden and springy to touch.

Allow cake to cool completely in the pan, then slice horizontally into two even layers. While cake cools, whip chilled cream with powdered sugar and vanilla until stiff peaks form. Slice half the strawberries for layering and reserve the rest for decoration.

Place bottom cake layer on serving plate. Brush lightly with strawberry jam. Spread a layer of whipped cream and arrange sliced strawberries evenly. Top with second cake layer. Apply a thin crumb coat of whipped cream over entire cake, then refrigerate for 30 minutes. Apply final layer of whipped cream, smoothing sides and top decoratively.

Decorate with remaining whole or halved strawberries. Dust lightly with powdered sugar. Refrigerate for at least 2 hours before serving to allow flavors to meld and cream to set.