Shrimpster!

In short, it is possible to make people you've never met or seen appear in your dreams. Usually this takes some time to build up the skill, but sometimes dreamers get lucky on their first try.

It is also possible to cause recurring dreams. Using dream incubation as Shrimpster suggested is one way. Another way is to use MILD (which is dream incubation with a tutorial, basically). Or you could use DEILD. I often "make" myself return to a recent dream using one (or more) of these techniques.

However, causing a dream to happen again and again over a series of nights usually takes a little more work and skill than making it recur on the same night it first happened.