Grease a 9x13 inch pan and set aside.1Preheat oven to 400°F.2In medium bowl use a hand mixer to beat three egg whites until soft peaks. Add powdered sugar and mix until combined.3In a separate large bowl, cream together butter and granulated sugar until light and fluffy. Add three egg yolks, beating after each one. Then add lemon juice and zest and combine.4In a third medium bowl, whisk together flour, baking powder and salt. Add to butter mixture and mix by hand just until combined. Then fold in egg whites. Pour into the greased pan and bake for 20-25 minutes until the top is browned.5To make glaze, heat raspberries over medium heat in a small pot on the stovetop until completely dissolved, about 5 minutes. Strain into a small bowl. Add vanilla to powdered sugar and gradually add raspberry juice until glaze is thin enough to coat the back of a spoon.6When cake is ready and still warm, frost with glaze. Let cool. Serve with more powered sugar as garnish.7