Add flour, sugar, salt, shortening (or butter) and orange/lemon rind into a large bowl. Whisk to combine; set aside.
Pour water into a mixing bowl; add yeast and stir. Let stand 3 to 5 minutes until foamy.
Add egg, egg white, and 1/2 of flour mixture to the yeast mixture. Mix on medium speed using an electric mixer (or a stand mixer with paddle attachment) for 2 minutes, or a wooden spoon/dough whisk until smooth. Stop mixer.
Add the remaining flour mixture and mix again with a spoon or dough whisk until smooth, 1 to 1 1/2 minutes. Scrape down batter from sides of bowl.
Cover; let rise in warm place until doubled, about 30 to 45 minutes.
Prepare topping. (see below)
Prepare pan(s): Grease one 9 x 13- inch pan, OR two 9-inch round layer pans, OR two 8-inch or 9-inch square pans.
Stir down raised batter in about 25 strokes; batter will be thick, somewhat sticky. Pour batter evenly in the pan(s)/ spread to edges of pan(s).
Prepare egg wash: whisk egg yolk and water. Brush over top of batter.
Sprinkle Topping evenly over batter.
With tip of spoon or fingertips, make little dents on the topping and press down almost to bottom of the pan(s). Tap pan(s) on table to settle the batter.
Cover; let rise until doubled, about 30 minutes. Preheat oven to 375°F.
Bake 30 to 40 minutes or until well browned (check after 20 minutes).
Remove from pan(s) and cool on wire rack.