Calling All Bakers

Now I have a chef for a son, I've gone to cooking schools in
France and I even worked for Sur La Table but I'll be darned if I can a super moist cake.  What is the problem?

I use butter, I use shortening, heck, I've used apple sauce.  What am I doing wrong? 

The absolute best, most moist cake I have ever made is actually a soda pop cake.  Do you believe that this is the best I could do?  It kills me because I like to bake from scratch; no cake mixes or premade anything.

So I am calling out to all bakers in blogland........help me with insights as to how to bake the moistest cake on the planet....................PLEASE!?