Beethoven’s 32 piano sonatas dominate his repertoire for solo keyboard. A little over a decade ago, English pianist Paul Lewis added his name to the canon of great pianists to record the entire cycle, with his Harmonia Mundi set rightly attracting rave reviews upon release. I count myself extremely lucky to have witnessed his performance of the legendary op. 111 sonata at Melbourne’s Recital Centre a few years ago, a breathtaking study in control, nuance, pacing and gut-wrenching emotion. So, when a Beethoven interpreter of Lewis’s stature turns his attention to a considerably less-lauded form of piano piece, one is advised to pay attention.

Although the literal definition of bagatelle (or trifle) seems to convey a sense of triviality, it can simply refer to something small, a minor thing (as opposed to a sonata, for instance) without being...