Directions

• Preheat the oven to 350 degrees. Butter and flour a 10-inch bundt pan. Set aside.
• In a large bowl, sift together flour, 1 cup granulated sugar, baking powder and salt. Set aside.
• In a small bowl, mix together egg yolks, oil, 2/3 cup grapefruit juice, lemon zest and vanilla. Mix this mixture into the flour mixture until smooth.
• In yet another large bowl, beat the egg whites with the cream of tartar until it forms soft peaks. Gradually add the remaining 1/2 cup sugar one tablespoon at a time and beat until it forms stiff peaks.
• Gently fold the egg whites into the cake batter and spoon it into the prepared cake pan.
• Bake for 40 to 45 minutes or until golden and tester comes out clean. Let the cake cool in the pan for 10 minutes and then invert it onto the serving plate. Set aside to cool completely.
• For the icing, combine the powdered sugar, 1 tablespoon grapefruit juice and mint. Add powdered sugar and/or juice to get the consistency you want. Drizzle the icing over the cooled cake and serve.