There is good and healthy Chinese food at Osaka Restaurant, in Pointe Noire. The average price for a meal was US$12-18. All meals were served in nice clean dishes, the restaurant is indoors and has AC, with a back-up generator, just in case. Some of the workers speak English and French.
There are several great restaurants in Brazzaville. Any taxi driver can take you to one of these nicer places 5000 - 15000 CFA. Most places are closed on Sundays. Expect beers to be overpriced here 1000 to 2000 CFA.