Dark Chocolate Chiffon Cake with Fluffy Rosewater Frosting

INGREDIENTS

1 1/2 cups

sugar

1 cup

all-purpose flour

3/4 cup

dark unsweetened cocoa powder

2 tsp

baking powder

1 tsp

baking soda

1/4 tsp

salt

eggs, separated, and room temperature

1/2 cup

vegetable oil (I used Sunflower oil)

1/2 cup

water, warm

1 tsp

pure vanilla extract

egg whites, room temperature

1/2 cup

(1 stick)(114g) unsalted butter, room temperature

2 cups

icing sugar (powdered, confectioners'), sifted

1 tsp

pure vanilla extract

1/4 cup

whipping cream (heavy cream, 35% fat)

1/8 tsp

rosewater, or more to taste (but use sparingly)

salt

Few drops pink food gel colour (optional)