Preheat the oven to 350 degrees F. Butter and flour a 9-inch round cake pan and line the bottom with parchment paper.
In a standing mixer fitted with a paddle attachment (or using a hand mixer), cream the butter until light and fluffy. Add the sugar and cream well. Add the eggs, vanilla, and salt and continue to mix well, scraping down the bowl with a rubber spatula occasionally. Fold in the sifted flour and pour the batter into the prepared cake pan. Bake until golden brown and firm to the touch in the center, about 25 minutes. Cool the cake in the pan on a rack. Unmold and, using a serrated knife, slice the cake in half horizontally into 2 layers.
To make Victoria Sponge Sandwiches: Dust your rolling pin and work surface with confectioners' sugar, and roll the marzipan into a disk the size of the cake. Using a knife, trim the marzipan to fit the circumference of the cake exactly. Spread the cut-sides of the cake layers with raspberry jam and sandwich the marzipan layer in between the jam-dressed cake layers. Press all the layers together; then cut into wedges, to serve. Dust the wedges liberally with confectioners' sugar.