Another recommendation from the lovely Robyn at Eating Asia was the Malay Kopitiam under the International Hotel and we met there for what was, without a doubt, the best meal of the trip.
We ordered everything from whole fried fish stuffed with onions and sambal to beef rendang, pineapple curry and my introduction to Kerabu salad http://rasamalaysia.com/coconut-and-chili-kerabu-salad-recipe/ which I was seriously impressed with. Definitely worth making the trip to Penang for!