This is truly a hidden gem.
The building is tucked into a busy street - it's easy to pass over, but it is well worth the stop. The decor is average - but you are coming here for the food, not the "experience".
I LOVED the pupusas - it was my first venture into this stuffed corn tortilla of bliss. I love both the queso, and the queso con loroco (an edible flower from a Salvadorian vine). At 1.99 - you can't go wrong.
Also, look for their chicken soup... this is like no soup you have had before. A friend had to clue me into ordering this, otherwise I would have never chosen it. Out comes a huge bowl of broth with corn, a starchy vegetable (maybe yuca), and carrot. On the side was a beautifully seasoned half of a grilled chicken. As I disassembled the chicken and added it to the soup with the rice - I was amazed by how incredible it was. It seems like they have this soup every other weekend - it alternates with the beef soup, which is not nearly as good.
The arepas are great, the sausage is also excellent.
The only thing left to be desired is their frozen bland french fries they serve with many items - skip these! They will happily trade them out for plantains!