I had big problems with the pop falling apart when I first started! Here are my top tips (all learnt the hard way!):
- As others have said, use the right amount of frosting as your binder. Some cake mixes (especially those labelled "moist") required very little. For one recently, I only had to use 2 tablespoons, whereas for previous ones, I used the 3/4 of a jar that Bakerella suggests. Add the frosting bit by bit, until you form a firm dough that is not too tacky but will roll together nicely.
- Make sure your cake balls aren't too big. If they are too large, they are more likely to falter under the weight of candy coating during dipping. I make mine about 1.5 inches in diameter. It is best to use a measure to get a consistent size. I'm not affiliated with them, but I use the OXO good grip small cookie scoop, which I find to be just right.
- Then chill your cake balls once you've rolled them. A couple of hours in the fridge or a short burst of 15 minutes in the freezer. Leave them out for a few minutes before you dip them though as they expand a little with the heat and if you dip them too soon, your beautifully dipped coating might crack. (Although adding a little vegetable shortening to your candy melts will reduce this risk and make for smoother dipping).
Very best of luck with your pops!