Tangerine Chiffon Cake
["5 tangerines or 3 large oranges", "2 1/4 cups cake flour (not self-rising)", "1 tbsp baking powder", "1 tsp salt", "1 1/2 cups sugar", "1/2 cup vegetable oil", "5 large egg yolks", "7 large egg whites", "1/2 tsp cream of tartar", "Tangerine glaze (recipe to follow)"]
["Preheat oven to 325 degrees.", "Grate 4 tsp peel and squeeze 3/4 cup of juice from the tangerines or oranges.", "In a large bowl, combine flour, baking powder, salt and 1 cup sugar, whisk in the oil, egg yolks, peel and juice until smooth."]
["oranges", "cake flour", "baking powder", "salt", "sugar", "vegetable oil", "egg yolks", "egg whites", "cream of tartar", "glaze"]