I will be in Argentina briefly next year and I want to know where the most authentic restaurants are in Buenos Aires that has great food but won't break my budget. Any suggestions?
If you want to try empanadas, wine, great meat, alfajores and mate all at once, I recommend the The Argentine Experience. It's great for meeting people and since it's closed doors, you get a very cool service, they will teach you words and expressions... it's very fun. For local and cheap restaurants, I always recommend Sarkis (Armenian food -- for me, the BEST restaurant in BsAs by far, super cheap and delicious), Salgado (pasta), Miranda, La Cabrera, Las Cabras, La Dorita (meat, parrilla), Burger Joint (for an amazing burger and great service), Malvon, Oui Oui(brunch). All of them are either in Palermo or Villa Crespo (neighborhood walk from Palermo).
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You can go to Las Cholas and La Colorada (Migueletes and Newbery) in Cañitas or Las Cabras in Palermo which are grill houses with some argentinian food like "humita", "pastel de carne" or "empanadas", they are charming and really cheap.
A friend of mine whose father is from BA and who goes there once a year told us about Freddy Restaurant Parrilla which is a little sandwich place by the San Telmo market. Crazy good, although totally unhealthy and I was a little skeptical about the cleanliness of it (it's basically just a little bodega-type place), but wow, would I go back in a minute! Great local find.