When someone brings you a problem, you usually know the answer. Giving it is fast, feels helpful, and is frequently the least valuable thing available.
They came with a question. They leave with an answer. Next time, the same shape of problem produces the same trip to your desk. Nothing transferred except the specific fact.
What transfers instead
How you narrowed it. "What did you already rule out, and why?" surfaces the reasoning, which is the reusable part.
Where you would look. Naming the source is better than reciting from it, because the source will still be there next time and you may not.
What you are uncertain about. People model expertise as knowing. Watching someone senior say "I am not sure, here is how I would find out" recalibrates that, and it is one of the more useful things you can demonstrate.
The cost, which is real
It is slower in the moment, and under deadline pressure you will not always be able to afford it. That is fine. The point is to notice that you are making a trade, rather than defaulting to the fast answer because it feels like help.
The people I have watched grow fastest were not given more answers. They were given more problems, slightly beyond what they were comfortable with, and a safety net they knew was there.