Is there anyway to make this in such a way as to serve as individual squares or mini-tarts? I'd love to serve at a party. THanks

The filing may be a bit soft for squares, especially at a party; 50 people with sticky fingers in the same room is no joke.

Absolutely, you could bake it in a square baking pan and cut it into squares. Or if you have tartelette pans, you can use them (though it would be more work and you'd want to trim down the baking time).