Joan's Rainbow Cake Recipe

 The Joan's Rainbow Cake has a very interesting backstory to it. The story goes like this " There was once a French lady name Juan waiting for her lover to come back from war. On the first day of her wait she makes a strawberry cake. However, he does not come that day. Hoping he will come the next day; she makes an orange cake. Again, he does not show up. On the third day she made a pistachio cake but like the other days he does not show up again. She went to bed disappointed that night but, to her surprise her lover came to her with a box of chocolates the next morning. Overjoyed, she combines all the cakes into one cake using whipping cream and melted the chocolates that her lover gave her and poured it on top of the cake. They ate it together in celebration of his return and their never-ending love.

INGREDIENTS FOR STRAWBERRY CAKE
Baking powder – 2 tsp
* Thick Strawberry Puree – 1/3 Cup
Yogurt – 1/4 Cup or (more yogurt or strawberry puree for batter consistency)
Sugar 2 tbsp + 1/2 cup
Whole Egg 1 + 1 egg white ,at room temperature
Unsalted butter 4 -5 Tbsp (57gms)
Strawberry extract or Vanilla Extract – 1tsp
Salt – 1/8tsp or A Pinch
Red Food Color – 2 drops

FOR PISTACHIO CAKE
Baking powder – 1 and 1/2 tsp
Pistachios – 1/2 cup (when soaked and grind with little water the quantity will be 1/2 Cup)
Granulated Sugar – 1/2 Cup
Thick Yogurt – 2-3 Tbsp or more for batter consistency
Egg – 1 whole Number + 1 egg white
Unsalted butter  4 Tbsp (57gms)
Pistachio extract or Vanilla Extract – 1 tsp
Salt – 1/8tsp or A Pinch
Green Food Color – 2 drops

ORANGE CAKE
Orange Juice Fresh – 1/3 Cup
Orange Rind – 1tsp
Baking powder – 2 tsp
Unsalted butter – 4-5 Tbsp (You can increase 2 more tbsps of butter)
Granulated Sugar – 1/2 Cup
Egg – 1 Number (whole) + 1 egg white
Thick Yogurt – 1/4 Cup (or more to attain cake batter consistency)
Orange extract – 1/2 tsp (optional)
Salt – 1/8tsp or A Pinch
Orange Food Color – 2 drops

Sources:

Joan's Cake Rainbow Cake With Whipped Cream Frosting - Nitha Kitchen (nithaskitchen.com)