Ron Choong had a thesis on this, I think. I have commonly understood the challenge of this paradox: Is it good because God commands it; or does God command it because it is good?
The solution is to refer to the attribute of God, the nature of God. Hence there is no need for a third option as William Lane Craig suggested (I am still perplexed with his "God and abstract objects" topic). The answer can go with either one provided that God is the source of good.