3/4 cup plus 1 Tbsp all purpose flour
1/4 cup cornstarch
3/4 tsp. baking powder
1/2 tsp. fine sea salt
3/4 cup sugar
10 Tbsp (1-1/4 sticks) butter
1 vanilla bean
1 large egg
1 large egg white
2 tsp. vanilla extract
1/2 cup sour cream
Position rack in center of oven and preheat to 325ºF. Butter 8-1/2 x 4-1/2 x 2-3/4-inch metal loaf pan. Dust pan with flour; tap out excess. Sift flour, cornstarch, baking powder, and salt into a bowl. Combine sugar and butter in large bowl; scape seeds from vanilla bean. Using electric mixer, beat sugar mixture until fluffy. Add egg, egg white, and vanilla extract, and beat until mixture is pale and thick. Beat in sour cream. Add flour mixture; beat until just blended. Spread batter evenly into prepared pan. Bake until tester comes out clean, 56-58 minutes. Cool in pan 15 minutes then completely on rack.
Cake Sharing 