I know someone mentioned Red Ribbon, but I prefer Little Quiapo for Filipino food more. It is off the beaten path and not as commercial, but delicious.

What about Sanai's? I live in the area and never went there until a friend introduced me to it recently. They have good Sangria, the food is okay (I have only eaten there once so I can't be a fair judge at this point), and I believe they have spaces they could set aside for groups. It is a short walk from the PATH as well.