A popular place
The Snack Sahas is on Saleh Salem Street, the main street that circles the historic district of Cairo. It's close to the 7th-century Ibn El As Mosque. It is a popular place where you can eat shawarmas, various kinds of sandwiches, and a large selection of vegetarian dishes like falafel, hummus, potato and tomato salad, and roasted eggplant. There's a wide variety of dishes and they serve them almost like tapas. You can also go eat in the room upstairs where there is a good view of the neighborhood. A full lunch with drinks is very cheap and goes for around 3 or 4 euros per person. If you do not know what to order, ask them to bring you a selection of dishes with pita bread.