According to Wikipedia, this is Gnocchi: http://en.wikipedia.org/wiki/Gnocchi
How do I know which beracha to make considering it is made from potatoes and is not a normal pasta? Should I just stick to she'hakol?
Gnocchi seem to be a form of pasta. See here 1, if made from the five species of grain (wheat, barley, rye, oat or spelt), make "mezonot".
If made from one of the five species and potatoes (or anything else for that matter), we need to know why one of the five species was used. (See here 2).
If it is added to add taste or nutrition AND it can be tasted – it would be the main part (ikar) and the brocho on the gnocchi is Mezonot.
If it is merely added as a binding ingredient to maintain a certain consistency – it would be secondary (tofel) and the brocho on the gnocchi would be shehakol.
Regarding saying shehakol in a doubtful situation, see here 3 which says, if you don't know which bracha to say because you didn't learn the halachot, you may not rely on on your lack of knowledge to say shehakol.. Rather, you should go and learn the halacha (or ask an authority) and then say the proper bracha.
Best is, of course, to CYLOR.
Gnocchi is a type of pasta. Though it might also have mashed up potatoes in it (which would lead one to think "shehakol") it still has substantial amounts of flour which, I would think, makes it a mezonos.
Just to add on to Avrohom Yitzchok's answer with a source: See here where it is quoted from the Sefer שערי הברכה that Gnocchi is Mezonos / Al Hamichya.
Gnocchi will never be eaten alone, there will always be a lot of cheese and spices and those are very important ingredients, I would go with shehakol