[fatum]

I believe this is what you're going for:

日本人の女の子は大好きです。

ローマ字：
Nihonjin no onnanoko wa daisuki desu.

I'm not sure if "onnanoko" is the correct word to use in this situation, but I think it is!

Of course you can also drop off the 私は (watashi wa), because the context is implied.