Located in a busy and lively street, this snack bar/restaurant has much to offer to both locals and tourists. Being in Lisbon for Business, I was told in numerous places to have a nice meal and what not. Often people forget that moving around huge cities like Lisbon can be chaotic at some points, and if you are located in one area of the city, there is no meaning to travel to another part of the city just to grab that bit between meetings. Often, in Lisbon, you will find plenty of small cafes or snack/bars that usually also offer lunch options (mostly targeted towards the locals who do not have time to go home and eat, or for those who do not have access to a canteen at their workplaces) I was woking on Rua Castilho the day, and i asked around locals if they know a place not far away, with some local ready to eat dishes for lunch. After three people telling me about Vontadinhas, I decided to check it out. The place, crowded with locals, was smelling with good and tasty food. I could see that almost everyone knew each other, and the waiters were also having a great contact with their clients. We decided to seat at the outdoor tables, and that was a great choice. Not only was it hot, and that allowed us to enjoy our meal in a very cosmopolitan area of the city (close to a huge park, shops and hotel) and feel the light wind touching our faces. 
We were suggested to try out the dish of the day (which everyone seems to be eating when we were there) - A picanha, Brazilian style steaks with a proper Portuguese salad and the usual french fries. Additionally, we sipped two local beers, and in the end, we pinched it all with the classic espresso. 
The waiters were outstanding, having some great energy and being polite at all moments. 
You will eat fast, you will eat well, and you will eat safely. The good thing about the place is that you can also eat at the counter - if you are really in a hurry, or you are alone for example), and you can also take your food away. For the price/quality ratio, I will give this establishment the highest rate I can. Thumbs up guys!