How to Make It
Preheat oven to 325°.
Coat a 10-inch tube pan with cooking spray; dust with 1 tablespoon cornmeal.
Place 1 3/4 cups sugar, butter, rind, and vanilla in a large bowl; beat with a mixer at medium speed until light and fluffy. Add egg yolks, 1 at a time, beating well after each addition. Beat in sour cream.
Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, 1/2 cup cornmeal, grits, salt, and baking soda in a medium bowl; stir well with a whisk. Add flour mixture to sugar mixture, stirring to combine.
Beat egg whites with a mixer at high speed until foamy. Gradually add 1/4 cup sugar, 1 tablespoon at a time, beating until stiff peaks form. Gently stir one-fourth of egg white mixture into batter; gently fold in remaining egg white mixture. Spoon batter into prepared pan.
Bake at 325° for 50 minutes or until a wooden pick inserted in cake comes out clean. Cool in pan 15 minutes on a wire rack; remove from pan. Cool cake completely on wire rack.