Carrot Cake with shells

1 1/4 cups room temperature unsalted butter 2 cups light brown sugar 5 large eggs , separated 1 orange, juice and zest of 1 teaspoon baking powder 1 teaspoon[...]

285 g butter , softened 285 g soft light brown sugar 5 large organic eggs , separated 1 orange, juice and zest of 170 g self raising flour , sifted 1 teaspoon[...]