Carrot Cake (The Best)

Cake

• 2 1/4 cups (560 ml) unbleached all-purpose flour
• 1 1/2 teaspoons (7.5 ml) baking powder
• 1/2 teaspoon (2.5 ml) baking soda
• 1/2 teaspoon (2.5 ml) ground cinnamon
• 1/2 teaspoon (2.5 ml) ground nutmeg
• 1/4 teaspoon (1 ml) salt
• 4 eggs, separated 

• 1 3/4 cups (430 ml) brown sugar
• 3/4 cup (180 ml) canola oil
• 1/2 cup (125 ml) orange juice
• 4 cups (1 litre) carrots, peeled and grated
• 1 cup (250 ml) walnuts, coarsely chopped
• 1/2 cup (125 ml) dried currants

Frosting

• 1 package 250 g cream cheese, softened 

• 2 tablespoons (30 ml) unsalted butter, softened
• 3 cups (750 ml) icing sugar