Well done bacon, so that it crumbles into little pieces when baby chews it, and it's easy finger food. I second the boiled chicken/soup chicken. Lox is also a good soft food (okay, so it's fish, not meat, but it's still protein).
I used to put the meat/meats on the grind button of the blender for a couple of pulse hits to moosh it down so it was not actually a paste but had some substance. ChowPup grew up to be 6ft 5inches and cuts his own meat now! Good luck.