Adding cocoa where it wasn't before

I found a great recipe for buttermilk chess pie in the Christmas with Southern Living Cookbook Volume 2 (1998, page 71). At the risk of copyright infringement, I won't reprint it. But I will say that I just mixed

• almost half a dozen eggs;
• 2 cups of that Splenda same-as-sugar stuff (because I'm trying to use less sugar, especially after the last few weeks);
• a dash of vanilla;
• 1 stick of butter;
• 2 Tbsp. flour; and
  
• 67% of a cup of buttermilk

and dumped it into a frozen pie shell. Then I baked it for about 50 minutes at 350 degrees and voila! It tasted like a dessert quiche to be honest, and there was a slight layer of either egg or buttermilk underneath the main part of the pie. I don't know if that was because I cooled it on a rack (like the SL editors suggest), but it didn't hurt anything.

After giving much of the pie to my hapless family (I can't eat the whole thing), I decided to try this again. But this time I replaced 1/2 cup of the "sugar" with cocoa powder. Damn, it was pretty intense for my taste. Very tasty. And that layer that settled between the pie and the pie crust was even more visible - a bright light yellow underneath the brown chocolate pie.

Source:
Southern Living. Christmas with Southern Living Cookbook, Volume 2 (1998: Oxmoor House, Birmingham, AL).