Preheat your oven to 350°F (175°C) and line a 15x10-inch baking sheet with parchment paper, lightly greased. In a large bowl, whisk 4 large eggs and 1 cup of granulated sugar until pale and thick, about 5 minutes. Stir in 1 teaspoon of vanilla extract.

In a separate bowl, sift together 1 cup of all-purpose flour, 1 teaspoon of baking powder, and a pinch of salt. Gradually fold this dry mixture into the egg mixture using a spatula, being careful not to over-mix.

Spread the cake batter evenly onto the prepared baking sheet and bake for about 12 minutes, until the cake springs back when pressed in the center.

Once baked, flip the cake onto a clean kitchen towel dusted with powdered sugar. Peel off the parchment paper and roll the cake up tightly with the towel while still warm. Let it cool in this rolled position for about 30 minutes.

Make the filling by whipping 1 cup of heavy cream until soft peaks form. Slowly fold in 8 ounces of melted white chocolate and 8 ounces of mascarpone cheese until well blended.

Unroll the cooled sponge and spread the filling evenly, leaving an inch along the edges. Drizzle with raspberry sauce and re-roll tightly, placing seam-side down on a platter.

Cover with plastic wrap and chill in the refrigerator for at least 1 hour. Decorate with whipped cream, fresh raspberries, or chocolate curls before serving.