Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius). Grease and starch a nine-inch round pan. Cut out a piece of Gefen Parchment Paper to size and place on bottom of the pan.

In a separate bowl, beat the yolks on high until they become light yellow in color. Slowly add 1/4 cup sugar and vanilla sugar. Add oil and slowly sift the potato starch in last (this helps prevent settling).

Gently fold the white mixture into the yolk mixture. Pour mixture into greased pan and bake 25–30 minutes. Remove from oven and allow to cool.

Beat eggs whites to soft peaks. Slowly add 1/4 cup sugar. Beat to stiff peaks.

Combine sugar and potato starch in a small saucepan. Whisk in the almond milk. Add egg yolks, vanilla, and salt. Bring to a boil over medium heat, whisking continuously until thick. Remove from heat. Transfer to a medium-sized bowl. Place plastic wrap onto the surface of the custard and refrigerate for 20 minutes.

Remove cake from pan. Remove parchment paper from bottom. Using a serrated knife, cut cake in half horizontally. Place bottom half of cake on a cake plate.

Spread evenly with the custard. (It may drip down the sides.) Top with remaining cake half. Refrigerate while preparing the glaze.

Heat the pareve whipping cream in a double boiler or a microwave (do not boil). Place broken chocolate pieces into the bowl and mix. Keep stirring until chocolate is melted and totally smooth.

When glaze is ready, quickly spread over top and sides of cake. Work quickly before it sets.