Love, love, love, love Tarranta.  It's an Italian/Peruvian fusion place and is absolutely delicious.  If you go there, highly recommend the pork chop (I don't even like pork and this thing was amazing) or the gnocchi with lamb ragu (my personal favorite).  It's not dirt cheap but the ambiance is great and the food is even better. 
For seafood Neptune is great as is Mare (a little less North End feel but delicious food). 

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I think Trattoria Il Paninio or Pagliucas on Parmenter St offer 2 of the best North End experiences. They are located right across the street from one another and both serve amazing authentic, home made style, italian dishes. They can both be busy, but every place in the North End is busy on the weekends. And these are far better than any tourist trap on Hanover... like Strega or Fiore. "

Bricco (Hanover St)
amazing Amatriciana Garganelli

NewYorkCityFeelings.com "

Trattoria Il Panino on Parmenter serves a delicious fettucini pesto :)
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Check out Trattoria Di Monica on Prince.  Small and intimate away from the touristy Hanover street.  Nice people there.  Absolutely try the Risotto!

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Prezza for Italian.

Neptune for Seafood.

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