Preheat your oven to 350°F (175°C). In a large mixing bowl, use an electric mixer to beat 4 eggs and ¾ cup of granulated sugar until pale and fluffy, about 5–7 minutes. Fold in 1 cup of flour, 1 teaspoon of baking powder, and a pinch of salt until just combined.

Line a jelly roll pan with parchment paper. Pour the sponge batter evenly into the prepared pan and smooth it out. Bake for approximately 12–15 minutes or until the top is lightly golden.

Let the sponge cool in the pan for about 5 minutes. Invert onto a clean kitchen towel dusted with powdered sugar and roll tightly while still warm. Let it cool completely.

Melt 6 ounces of white chocolate in the microwave in 30-second intervals. Beat 8 ounces of mascarpone cheese until smooth, add melted chocolate and mix well. Fold in 1 cup of whipped cream until combined.

Blend 1 cup of fresh raspberries in a food processor until smooth, then strain through a sieve to separate the seeds, collecting the raspberry sauce.

Unroll the cooled sponge, spread white chocolate filling evenly, drizzle raspberry sauce, and roll back up into a log shape.

Wrap the assembled log tightly in plastic wrap and refrigerate for at least 1 hour to meld flavors.

Dust with powdered sugar before slicing. Serve with extra raspberry sauce on the side.