First things first: try egg coffee at the iconic Giang Cafe where, according to the legend, egg coffee was born when the owner ran out of milk and had to create his own concoction as an alternative. It’s easy to miss the entrance to this humble but perpetually busy family-owned coffeeshop, but it’s worth looking for. 
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This is one of the most famous places among the locals for Pho, the traditional noodle soup.  Don’t forget to add lime, chilli and vinegar to your bowl or just copy Vietnamese people next to you for the authentic pho experience.  Pay at the entrance 60,000 Dong and you will get your soup. 
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This place is such a gem! Not only you get to try Vietnamese desserts but the  staff is just so nice! They take time to explain every dish and are happy to answer any questions.  The durian bowl I had was delicious and the owner explained that you have to eat it with ice which is served on a side.  The second time around I had the Traditional Bowl, which included different types of beans and glutinous balls.  Very delicious and filling!  I think it would make a perfect breakfast.
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This is a very small street restaurant in a nondescript alley of Hanoi Old Quarter, loved by the locals, but not many tourists have ventured into this delicious territory. Two must try dishes there is Bun Ca and Ca Cuon Thit.  Bun Ca is the traditional noodle soup with deep fried fish which somehow stays crispy.  Do not miss out on Ca Cuon Thit: deep fried fish balls, which are just divine, but come early to get yours, since these are in high demand.  You will be seated on the tiny plastic chairs right in the middle of the street and will get a chance to experience truly authentic Vietnamese cuisine.  If I’m ever back in Hanoi, this is the first place I am going to visit. 
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Give coconut coffee a try or experiment with Vietnamese coffee (I like mine served cold) or just go straight for that cappuccino.  Filled with Hanoi locals, it is a pretty comfortable spot to sit down and watch street life go by.  There is a second floor balcony, be sure to check it out if downstairs is too crowded.  Very nice staff in this cafe as well: forgot my book and had it returned to me when I came back for a cup the next day.
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20 Hàng Bồ Street 
This super inconspicuous bakery in Hanoi Old Quarter is full of delicious goodies at the right price.  Pick a bunch at random and you would be surprised how satisfying they are.  A must for anyone craving that gluten.
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