Best pizza in Madrid! You may say it's a very small and not particulary nice place (I would say it's authentic), but I can assure if you like pizza (argentinian style) you really have to go.
My recommendation: try the superespecial or El Trebol. And ask for the hot sauce.
You should be around 9 pm or after 10:30 because the place is so small that it's impossible to have dinner where there are more than 12 people. Of course, you can't make a reservation ;)
Phone number: +34 915 212 153