In my experience the Sofitel has the best food I've had in Manila - I guess not surprising, they're French. However both their incredible buffet dinner inside and the one by the pool are just excellent and focus on Filipino food, especially the outdoor restaurant.
I will agree with previous posters that Filipino cooking is nothing to write home about - as someone said 300 years of Spanish cooking "improved" by 50 years of American cooking. Not a good recipe !!!!