I think they easiest way to grasp it is by writing simple examples, eg write a function that prints the last item in a list and returns the rest and then call it recursively to print the whole list. You can do it in about 5 lines in python or js and thinking it through often helps to grok stuff. I just did that myself and on the 5th attempt it worked(!).

I had two A-level maths teachers at school. One always started by getting the class to do a simple as possible example like the above before launching into more complicated stuff, the other started off explaining complex stuff. The first approach worked far better, with the second our minds just kind of glazed over.

There's something a little counter intuitive about it like your neurones have to wire up on the simple example before getting the more complex. Doing the simple stuff then sleeping on it and doing the complex the next day works better still I think.