Prepare the sponge cake first; this can be done one day in advance, too. Line a 12x17-inch jelly roll pan with parchment paper; do not grease the sides. Preheat the oven to 350F. Place the eggs, sugar and vanilla into a stand mixer bowl and whisk on high speed for 7 to 8 minutes, until the eggs are voluminous, thick and pale in color.
Combine the flour and baking powder, then sift the dry ingredients into the eggs in small increments, folding gently but thoroughly after each addition. Pour the batter into the prepared pan and bake in the preheated oven for 18 to 20 minutes, until the cake is golden brown on top. Remove the cake from the oven and cool completely on a wire rack. Once cooled, remove the cake from the pan and remove the parchment paper. Use a pastry brush to soak the cake generously with the peach juice/wine, then cut into small squares using a serrated knife.
Next, prepare the custard. In a medium-sized mixing bowl, whisk together the egg yolks and sugar vigerously for 3 to 4 minutes, until the mixture is thick, pale and ribbons off the whisk; set aside. Into a separate sauce pot, pour in the milk and add the cornstarch. Cook the milk over medium heat until it's steaming hot but not boiling.
Temper the hot milk into the egg yolks, adding a little at a time and whisking after each addition. Pour the resulting mixture back into the sauce pot and cook over medium heat, stirring constantly with a rubber spatula, for 4 to 5 minutes, until the custard has thicken and holds its shape. Remove the custard from heat and add the butter and vanilla. Whisk the custard until the butter is completely melted, then cover with plastic and refrigerate until completely cooled.
Next, prepare the cream cheese frosting. Pour the chilled heavy cream into a stand mixer bowl and add the sugar and vanilla. Whisk the cream on medium to high speed for 3 to 4 minutes, until stiff peaks form. In a separate bowl, cream together the softened cream cheese and butter for a few minutes until smooth. Add the melted white chocolate and mix again for a few minutes until smooth.
Add the cream cheese mixture to the whipped cream and whisk again on high speed just until well combined. Do not overmix!!
Prepare a large bowl for assembling the cake, approximately 10 to 12 inches in diameter. Line the inside of the bowl with plastic wrap, leaving about 6 inches extra on the sides. First, arrange the fruit on the bottom and along the sides of the bowl. Next, spread a generous amount of the cream cheese frosting over the fruit, sealing the fruit in place. Then, add a layer of sponge cake, spread a generous amount of the custard over the cake and add another layer of fruit. Repeat this process until the bowl is filled. Finish the top with the cream cheese frosting.
Bring the extra plastic wrap up and over the cake, sealing the cake in the bowl. Add extra plastic if needed. Refrigerate the cake for a minimum of 4 hours, or leave it to set overnight. When ready to serve, invert a cake stand over the bowl, then flip right side up. Carefully lift up the bowl, then peel away the plastic. Use a serrated knife to cut and serve the cake.