If you have a penchant for something, you like it very much and you keep going back to it — a leaning of taste, not a one-off. She has a penchant for terrible puns; he has a penchant for late nights. We borrowed the French word as-is, from a verb meaning 'to tilt' or 'lean', so the picture is that your taste leans that way. It is a little formal or writerly: in speech, most people would just say they really like something, or they are into it. You almost always say a penchant for + a noun. Though actually you will hear penchant to do among some speakers; careful writing still prefers for. It is stronger than a mild preference and lighter than an addiction — a habit of liking.