[_] [B] [_]
[_] [P] [_] = [H] 
[_] [_] [_]

P=pie base B=beef  H=Steak Pie
Steak Pie

[_] [B] [_]
[_] [P] [_] = [H] 
[_] [_] [_]

P=pie base B=porkchop   H=Pork Pie
Pork Pie

[_] [B] [_]
[_] [P] [_] = [H] 
[_] [_] [_]

P=pie base B=chicken   H=Chicken Pie
Chicken Pie

[_] [B] [_]
[_] [P] [_] = [H] 
[_] [_] [_]

P=pie base B=cheese slice   H=Cheese Pie
Cheese Pie

