1 cup all-purpose flour
1/2 cup (1 stick) butter, at room temperature
Preheat oven to 350 degrees F. Grease a 9-inch round cake pan with butter. Add a round of parchment paper and grease again with butter.
Combine flour, baking powder and salt. Combine butter, sugar, orange rind and vanilla in a stand mixer. Blend on medium speed until well combined. Add eggs one at a time, beating after each addition. Reduce speed to low and add flour mixture and cornmeal alternately with milk, beating just until evenly incorporated. Scrape into prepared pan, spreading evenly.
Bake 30 minutes or until a tester inserted in the middle comes out clean. Cool in pan on wire rack. Invert, remove parchment paper and flip to top side. Slice and serve when cool.