GLAZE:
1/3 c. light brown sugar
1/4 c. unsweetened Dutch process cocoa powder
1/3 c. lowfat milk
1/4 tsp. vanilla
6 c. fluted tube pan sprayed with
vegetable oil spray
Preheat oven to 350F.
Position rack in lower third of the oven.
On low speed with an electric mixer, mix the sugar,
flour, cocoa, baking powder, baking soda,
and salt until thoroughly combined.
Add the softened butter, whole egg, and egg whites.
Set a timer for 2 minutes as you begin
beating on medium speed.
As soon as the dry ingredients are moistened,
increase the speed to high and continue mixing
until the 2 minutes are up.
Stir the optional espresso powder into the yogurt,
if you are using it.
Add the yogurt and vanilla to the batter.
Beat at high speed for exactly 2 more minutes.
Scrape the batter into the pan.
Bake 30-35 minutes or just until a thin wooden skewer
inserted in the center of the cake comes out clean.
Do not over bake. Cool in the pan on a wire rack
for ten minutes before unmolding on the rack to cool completely.
Serve sprinkled with powdered sugar.

Make the Glaze: In a small heavy bottomed saucepan,
combine the brown sugar with the cocoa.
Use a wooden spoon to stir in just enough milk
to form a smooth paste. Stir in the remaining milk. Cook over medium heat
until mixture simmers, and finally begins to boil,
stirring constantly and scraping the sides and
bottom edges of the saucepan religiously.
Boil gently for 1 1/2 minutes,
stirring constantly to prevent burning.
Off heat, stir in vanilla.
Cool to room temperature. Spoon glaze over cake.