Miguel Angel Benedí
Bocadillos next to Prado de San Sebastián station
If you are going to or coming from Prado de San Sebastian station and want to eat something cheap, I recommend el Rey de los Bocadillos (the king of filled rolls).
It is 20 meters from the station and from the outside it may seem like a Charcuterie, but no, they do cut the sausage for the bocadillos right in front of you however!
The deals are amazing: pork tenderloin bocadillo, cheese and bacon rashers + potatoes + Pepsi + cupcakes are 3 € and really nice.