I just bought cheap scales of ebay. I don't measure in cups in more if I can avoid it. This is the recipe
http://fromscratchsf.wordpress.com/2011/07/26/white-cake-part-3-with-recipe/
Hi, twice I've made Scratch SF recipe for vanilla cake. It's pretty good, moist and has plenty of flavour. I make the version with egg whites, butter and milk.
I can't really call it a white cake as the use of butter...
Try boiled condensed milk (dulce de leche) or just caramel sauce in swiss meringue buttercream! So yummy!! That's how I make it all the time. But condensed milk can get a bit pricey after a while, so I just use homemade caramel sauce...
Did you use simple syrup on your cake? Because the could be your problem. I use ganache and fondant together and I've never had that happen. Although I put my ganached cakes it the fridge to harden up (Just so I know it's really firm!).
I have seen where the centres (after being cooked) have been cut out with an apple corer, then filled with ganache. You can then plug with a little of the cake that was cut out (or not) before icing.