Arg.  As a self-proclaimed "real" baker I am determined to never use a boxed cake mix but I have yet to find a recipe that comes out as light, moist, and fluffy.  I've tried many MANY recipes and can't seem to find one I really like.  The two I like the best so far both call for egg whites but often come out dry.  I read that over beating the egg whites can cause this  but I assure you they were not over-beaten as they never really even stiffened up.  I guess it's possible that I over baked the cupcakes although I only left the cupcakes in 18 minutes (the lower end of the time scale) and the knife JUST came out clean.  When making the recipe I added extra milk because the batter looked more  like cookie dough so I felt it needed to be thinned out.  Any ideas?  Any remedies?

what is your recipe?
 

AHeavenly white cake: 2 3/4 C sifted cake flour, 4 tsp baking powder, 3/4 tsp salt, 4 egg whites, 1.5 C sugar, 3/4 C butter, 1 cup milk, tsp vanilla, tsp almond. Lemon cake: 2 C cake flour, 2 tsp baking powder, 3/4 tsp salt, 1 C sugar, 3/4 C milk, 3 egg whites, 1/4 cup more sugar for making the meringue, 1 tsp lemon extract.

The only recipes I've made that come out dry involve egg whites....folding meringue into the batter. I've found in reading that egg whites can be drying and you shouldn't over best the eggs...so at best I probably under beat them (as I find it difficult to get the whites to stiffen back up after adding the sugar anyway). In both recipes more milk is added....in the first recipe it's because the reviews said to...in the second recipe I did it because it came out thick like cookie dough and so I added probably 1/4 cup more milk. Again, don't think I over baked them...but could certainly try less time in the even.

I would start with the Heavenly Cake and go from there.  Are you sifting first and measuring after?  This can make a huge difference in the amount of flour.  Most reviewers recommended upping the liquid to 1.5 cups.  Beat the butter and sugar until light and fluffy.  The meringue should get to be soft peaks after the addition of sugar.  Then fold in, don't just mix it in.

My guess is, that it is one of the above that is getting overlooked in this recipe.  You'll probably have one of those "aha" moments on this one.
 

Thanks so much!  I have made it where it came out OK once or twice,  and am not ready to give up on this heavenly White cake recipe as I really like the flavor.  I will try your suggestions, thanks!!!