Grease the bottom and side of an angel food cake pan, 10 X 4 inches, 12-cup bundt cake pan, or a 9 X 5-inch loaf pan with shortening and flour (I used nonstick cooking spray).
Beat sugar, butter or margarine, lemon extract and eggs in a large bowl with an electric mixer on low speed for 30 seconds, scraping bowl constantly; beat on high speed for 5 minutes, scraping bowl occasionally.
Mix flour, baking powder and salt; beat flour mixture into sugar mixture alternately with milk on low speed, beating just until smooth after each addition; fold in lemon peel and poppy seeds; pour into pan.
Bake angel food or bundt cake pan for 1 hour and 10 minutes to 1 hour and 20 minutes; loaf pan 55 to 60 minutes, or until a toothpick inserted in the center comes out clean.
Cool 20 minutes; remove from pan to wire rack; cool completely, about 2 hours.