Prep 2 lb cake pans with parchment (not wax).
Line bottoms evenly with marmalade.
Cream butter, sugar, and zest thoroughly.
Add eggs, scraping. Mix thoroughly but not excessively.
Mix salt, cayenne, black pepper, flour, corn starch, baking soda, set aside.
Mix soy milk, lemon juice, citrus extract, set aside.
Alternatively add solid mix and liquid mix, scraping as you go.
Make 3 layer cakes with lemon curd and rich icing and decoration.