Beat butter and cream cheese together until well-blended. Add sugar and beat until light and fluffy. Add eggs, one at a time, beating well after each addition. Blend in vanilla. Sift flour and salt together and blend into the creamed mixture.
Spoon batter into prepared pan.
Bake 1 hour 30 minutes or until toothpick inserted 1 from edge comes out clean.
Cool in pan 5 minutes. Turn out onto wire rack and cool completely. Dust with confectioner’s sugar if desired.