Japanese Cotton Soft Cheesecake

mascarpone

heavy whipping cream

caster sugar (super fine sugar), watch my instagram video to see how I make this out of granulated sugar

large eggs, separated

vanilla bean, split and seeds scraped

Zest of one orange + 2 tablespoons orange juice

flour (I used gluten-free all-purpose, but wheat flour is what Silvia originally calls for)

corn starch (corn flour)

berries, plus more for serving

salt

cream of tartar