FROM CGTALK
I think I figured it out.
This is the process:
1. get liquid looking how you'd like
2. cache liquid (default cache control: 1)
3. select container -> add foam
4. get foam looking how you'd like
5. check 'Enable' in Foam Cache tab -> Cache Control set to 2
6. run timeline for length of cache
7. Change Cache Control to 3
Voila! The problem before was that I went to the BiFrost menu bar and tried to recache everything - and Maya was asking if I wanted to replace or rename existing cache - neither of which I wanted to do.
