Mencho is Mozes’s own. Not a standard handed down through the tradition, but a song he wrote himself, and one that has travelled: it turns up in his trio concerts and is an absolute hit with any audience.
What makes it worth learning is the craft in it. The melody is warm and singable, the kind you can hum back after one listen, and underneath it sits a chord sequence with real modern Gypsy Jazz character. That combination is interesting to study. There is enough shape in the tune to hold on to, and enough movement in the harmony to keep your solos interesting.
In these lessons Mozes takes his own composition apart from the ground up: the chords and the way he likes to pick them, the theme with Daniel Rosenberg on rhythm guitar, and then four solos climbing from short melodic phrases all the way to octaves and a chord solo. Learning a piece from the person who wrote it is a great thing. Take your time and enjoy!