Preheat oven to 325 degrees.
In large bowl, use a hand mixer or large spoon to cream together softened butter and sugar until well combined. Mixture will look white.
Add eggs one at a time. Stir until well combined before adding next egg. Repeat process until all 5 eggs have been added.
Add vanilla (or lemon) extract, sour cream, lemon juice (or lemonade concentrate). Stir until well combined. Set aside.
In medium sized bowl, sift together all-purpose flour and baking powder.
Add flour mixture to wet ingredients. Stir until well combined. Set aside.
Use baking spray with flour to grease a 12-cup cake pan. Grease tube, bottom and sides.
After pouring cake batter into cake pan, tap pan on counter to help it evenly.
Bake 1 hour and 30 minutes OR until a long knife or skewer inserted in center comes out clean. Oven temperatures vary. Decrease temperature 25 degrees if cake's edges brown after 20 minutes in the oven.
Test for doneness by inserting knife or long skewer into center. Press to bottom. Cake is done if it comes out clean.
Cool in cake pan at least 10 minutes before inverting on a plate.
Drizzle glaze over cool cake.