I'm looking to make some meat pies to bring to a Nigeria-themed pot luck. The ones I'm thinking would be good would be like the ones I've had at the Bronx zoo in their "Africa" area-- they are square pastries, about 4 inches across, with a filling that includes ground beef. The filling is moist and somewhat spicy. Any good ideas out there on how to create the filling (I'm not worried about the pastry). I'm not sure what the right set of spices would be.