Mix all the sauce ingredients together and place in a saucepan. Cook over low heat until peanut butter melts. Simmer for 10 minutes. If the sauce gets to thick, thin with a little water or chicken stock.
Brush the naan with melted butter, top each with the mozzarella, chicken, scallion, sauce and cilantro. Place on a baking sheet in the oven for 10 to 15 minutes, or until cheese has melted. Serve immediately.