Owen Barfield often used the phrase "Thinking about thinking" in a technical sense - but here I am talking in more general terms about a way of pursuing one's own personal destiny in this mortal life.
The idea is that the purpose of this mortal life - in the sense of explaining why it is we remain alive, sometimes for many decades (rather than dying and - if a follower of Christ - going to Heaven) is to learn; and what we are learning is tailored to what we each as unique individuals, most need to learn (from a eternal Heavenly perspective).
We are able to do this because God - as creator - ensures that sooner-or-later we will have the relevant and necessary kind of experiences from-which we can learn. God cannot 'make us learn' - we need to do that for ourselves, we need to make the right choices, to discern Goodness and recognize sin, and repent etc. - but God can 'feed' us with the experiences from-which relevant learning is best done.
These experiences may come in our external lives - in physical or social events; via people, illness, challenges, creative work or whatever. But experiences can come in other ways - such as dreaming. Thus we can, one way or another, experience anything that we need to experience.
Another way is in thinking - we may find ourselves thinking some-thing or another, in a powerful, recurrent, obsessive or whatever fashion - this thinking may be virtuous, sinful or not obviously either of these.
But whatever it is that we are thinking about a lot, whatever we find ourselves brooding upon, ought to be taken seriously and in a conscious fashion. Because this is experience, and we are meant to learn from it.
Probably it is something we need to decide-about. Something that may point-ahead virtuously, or something we need to clarify and reject. Or, the thinking may be general, vague - yet contain some particular thing that needs to be recognized and discerned.
My point is that we can always, whatever the situation - and however apparently dull and uneventful - be learning from our thinking; and this may be of extreme importance to our mortal earthly life.