Is there a best practice or recipe for migrating a two database CiviCRM installation into one database?
I managed to resolve this dilemma.

The goal was to move a 2 database Drupal/CiviCRM website into the CiviCRM Starterkit platform which requires that Drupal and CiviCRM use a single database. I was not able to import my database dump into the existing Drupal website because although I had set foreign_key check to zero, I was receiving a "Cannot add foreign key constraint" error.   

My solution was as follows:


Download a dump of the CiviCRM database with ignore foreign keys, drop tables, triggers etc. 
The dump does not include tables for: civicrm_acl_cache, civicrm_acl_contact_cache, civicrm_cache, civicrm_domain, civicrm_group_contact_cache
Remove the drop tables statements before importing. Leave in: IF NOT EXISTS create table.
It was important to Truncate tables before each table's data insert statement.
When I ran the import shell command the import would stop because the Log Tables didn't exit. They are in the Dump but they were not being created so I ran all of the IF NOT EXISTS create table commands before running the import command. 


Once I had accomplished the above 5 items, I was able to run the import and populate the tables. All is well.

I hope this helps anyone else who runs into this challenge.