ATMOSPHERE: Patati Patata is a very small restaurant on the corner of St-Laurent. It has a rather "vintage" ambiance. In my opinion it is quite cramped but it wasn't unbearable. I would recommend coming at quiet hours.
FOOD: The food was very good and the quality was okay. But it's comfort food so I wasn't expecting a high-class meal. I got the Tofu burger (which I would not recommend) but my friend got the cheeseburger and it seemed pretty tasty. The fries were decent as well.
PRICE: Honestly, you won't find cheaper than this, especially for the quantity/quality that you're getting. Portions aren't the biggest but that's normal for this kind of place. Burgers are around 2-3$ and fries as well. I'd rather come here than go to McDonalds for sure.
SERVICE: The service was very nice. It had a "family-owned" restaurant feel to it. The main chef was pretty sweet and efficient.