Preheat oven to 325° F. Butter and flour 12-cup angel food cake pan with removable bottom, or use a 12-cup Bundt* cake pan.
Using electric mixer, beat butter in large bowl until fluffy. Gradually beat in sugar, then lemon zest, lemon extract and salt. Beat in eggs, one at a time. Add flour in three additions, beating just until blended each time.
Transfer batter to prepared pan. Bake cake until a golden color and tester inserted near center comes out clean, about 1 hour.
Cut around center tube and pan sides of angel food cake pan to loosen cake. Remove pan sides. Cool cake completely.
*If using a Bundt cake pan, cool cake in pan 5 minutes. Turn cake out on rack; cool completely.