Separate the egg yolks from the whites. Beat the egg whites until stiff peaks form. In a separate bowl, beat the yolks with the sugar for at least 10 minutes. Add the almond flour, potato starch, lemon zest, baking powder, and vanilla powder. The batter will be very thick.

Fold in the beaten egg whites. The batter will become smooth and soft. Grease and flour a 9-inch (24 cm) cake pan and pour in the batter. Bake at 350°F (180°C) for 30–40 minutes. Check doneness with a toothpick.

Let the cake cool. Prepare the glaze by mixing the two packets of powdered sugar with a few drops of orange blossom water and a few drops of red food coloring to achieve a light pink color. The glaze should be thick and opaque; if it’s too thin, add more powdered sugar.

Spread the glaze over the cake. Then prepare the royal icing by mixing powdered sugar, lemon juice, and egg white. Whisk until the mixture is thick enough to hold its shape (when you lift the whisk, the icing should fall in ribbons). Use a piping pen or make a piping bag from parchment paper with a small tip to decorate the cake as you like. Add some silver dragées for decoration.