Orange Cake with Yogurt Sauce

Ingredients

• 1-3/4 cups (425 mL) all-purpose flour
• 1/4 tsp (1 mL) salt
• 6 egg whites
• 1-1/2 cups (375 mL) sugar (divided)
• 6 egg yolks
• 2/3 cup (150 mL) orange juice (divided)
• 1 tbsp (15 mL) grated orange peel
• Icing sugar
• 1-1/2 cups (375 mL) regular or low fat orange or lemon yogurt