The joy of a hearty, simple dish like donburi is that once you've mastered the basic technique, it's easy to start changing some of the variables and experimenting. The other night I followed my usual recipe for chicken donburi but used chicken thighs rather than breast meat. Knowing that this would give a stronger flavor to the completed dish, I decided to use shrimp stock as the base for the broth, rather than dashi (shrimp stock recipe from Mark Bittman's How to Cook Everything). I also added a few drops of pepper sherry to the broth.
As expected, the shrimp stock enhanced the darker flavor that chicken thigh meat gives to donburi. The pepper sherry was not noticeable in the broth, so I guess I need to use it less timidly next time. I'm still deciding if I like it this version of donburi or not, but playing around like this is part of what you do when you start making a dish your own. Besides, donburi is forgiving.