The great pianist Paul Badura-Skoda counts the first movement of this B-flat major sonata K. 333 as “among the most beautiful … in the piano literature.” And who would want to contradict him? What a pyrotechnic display of wonderful and freely vibrant melodies in the first movement, artfully coupled with pianistic runs and flourishes! The sublime slow movement (“Andante cantabile”) could pass as the piano reduction of a string quartet, while the concluding “Allegretto grazioso” is like the jaunty but subtle dance finale from an opera buffa. As we know today, Mozart composed this miraculous sonata in 1783 – previous Mozart scholarship missed the mark entirely with its much earlier date. It appeared in print a year later, interestingly in combination with the (relatively) early piano sonata K. 284 and the grandiose violin sonata K. 454.