Some of your suggestions were very very very disappointing. Applebees, Dominos, Chili, Dunkin Donuts and Krispy Kreame? Really?? I thought the Lebanese were more refined. Here's my picks. I don't know if these places are still open or not, I haven't lived in Lebanon for 10 years now.
Bedo in Burj Hammoud
Chez Sami in Jounieh
El Qanater in Mazraet Kfarzebian/Fakra
Snack A Van at NDU Old Campus (I'm dreaming if they're still there

)
Pizza Napoli on Bcharri's road (Kousba maybe?)
Sea Sweet
Super Schtroumpf
Any restaurant in Ouyoun Orghosh