Mix cream cheese, blue cheese, milk, bacon, chives and pepper.
Spread half of cream cheese mixture evenly over 1 tortilla. Layer a third of roast beef, salad greens and tomatoes (in that order) on tortilla, leaving space at one side covered only with cream cheese mixture. Beginning at side covered with fillings, roll up tightly. Repeat with remaining tortilla, cream cheese mixture and fillings.
Serve immediately, or wrap securely with plastic wrap and refrigerate no longer than 24 hours.
Serving suggestion - if making into appetizers, can also cut ends with no filling off of wrap, and then cut wrap into 5 pieces to make individual spirals.