Preheat the oven to 350ºF. Sift the flours, baking powder and cornstarch together.⠀
Separate the egg whites from yolks. Beat the whites with monk fruit at high speed for 7 minutes until stiff peaks form.
Beat the egg yolks with vanilla, and gradually add flour mixture just until incorporated.
Slowly mix in the egg white mixture to the egg yolk+flour mixture with a rubber spatula. Need to be careful not to overmix, so it stays fluffy. Mix just until incorporated.
Bake at 350ºF for 45 minutes.
Beat the cream ingredients at high speed for 3 minutes.
Divide the sponge cake into 2 equal parts and start assembling.