Which country is Mountain chicken the national dish?

Mountain chicken is not the national dish of any country.

It's actually a type of frog, and the name is used for several species of large, edible frogs found in the Caribbean.

There is some confusion because it's a popular and traditional dish in Dominica, but it's not officially recognized as their national dish. Dominica's national dish is actually Sancocho, a hearty stew made with various vegetables and meats.