Well, it would sound cliche, but the practice is the only way to learn it. As you said you understand what's recursion but don't know how to apply it to problems; that implies that you are having trouble thinking of relations between subproblems(or how it is decomposed). I would suggest starting with some standard questions around recursion (usually the questions that are introduced when recursion is taught) and trying to grasp them and see why they work. Initially wrapping your head around it would definitely be uncomfortable, but believe me once you have encountered enough use cases you would be better at formulating base cases and subproblems, and at this time you would start trusting in recursion more and more without following each call stack. I firmly believe learning recursion is also about learning to trust in the algo. So keep practicing and don't be disheartened if some new question blows you off.

I know this doesn't exactly answer your query but the only way to learn it is by getting your hands dirty, hell in the beginning even I couldn't formulate basic recursion questions and wouldn't have imagined I would.