Preheat oven to 180 °C (350°F). Grease 38x26 cm (15x10 inch) baking pan with butter, then line it with baking paper so the cake seamlessly releases. Grease the baking paper too.
For the sponge, sift the flour, cornstarch, and baking powder into a large bowl.
Using a hand mixer or a stand mixer beat the egg whites with half of the sugar and pinch of salt on high speed for 5 minutes or until stiff peaks form. Set aside.
In another bowl, beat the egg yolks, rest of the sugar, and vanilla extract, until pale, about 2-3 minutes. Add in the melted and cooled butter and beat 30 seconds. Add in half of the dry ingredients and mix until incorporated. Using a rubber spatula gently fold in beaten egg whites until half-incorporated, then fold in rest of dry ingredients until fully combined and there are no visible streaks of flour or egg whites. Avoid over-mixing.
Spread batter evenly into prepared pan. Bake for 9-10 minutes or until the top of cake springs back when touched.
Place a kitchen towel on a flat surface and dust it with powdered sugar. Gently turn baked cake onto a prepared kitchen towel, peel of the top layer of baking paper. Slowly roll the cake with a kitchen towel, rolling from the short end to the other short end. Let the cake cool completely.
For the sauce, combine raspberries, sugar, and lemon juice in a saucepan over medium heat; cook and stir until raspberries break down, sugar dissolves, and sauce thickens, around 7-8 minutes. Remove from heat and press sauce through a fine-mesh strainer to remove seeds. Cool to room temperature, cover the bowl with plastic wrap, and refrigerate until chilled, at least 45 minutes.
For the filling, using an electric mixer, whip the cold heavy cream into stiff peaks on medium-high speed, about 4-5 minutes. Set aside.
In another bowl, beat the cream cheese and powdered sugar together on medium speed until perfectly smooth and creamy. Fold in whipped cream into a cheesecake filling.
To assemble, gently unroll the cooled cake, spread the raspberry sauce into an even layer, then spread the cheesecake filling over the sauce (you will be left with a few tablespoons of the filling, use it to decorate the top of the roll cake). Sprinkle fresh raspberries over the half of the filling, then re-roll the cake this time without the kitchen towel. Wrap the roll cake with a plastic foil, and refrigerate for at least 1 hour before slicing and serving. Dust with powdered sugar, or decorate to your likening.