How do i make alcappurias?

THIS IS A YUMMY APPETIZER FROM PUERTO RICO. I KNOW HOW TO MAKE THE MASA BUT NOT THE MEAT. I HAVE MADE IT WITH PICADILLO (GROUND BEEF). NOT LOOKING FOR THIS FILLING. I LIVE IN THE CHICAGO AREA AND THEY PUT SOMETHING ELSE IN IT AND I DONT KNOW WHAT SPECIFIC MEAT IT IS AND HOW TO COOK IT. IM LOOKING FOR WHAT KIND OF MEAT AND HOW TO COOK IT. ANYBODY KNOWS? THANKS TO ALL THAT REPLY.