I recently went to the Giraffe restaurant in Kings Cross, London for the second time within 2 months and I have to say, I really like it here!! I love the relaxed atmosphere especially as it is located right within Kings Cross station and the service has always been very good, and fast!
My boyfriend and I ordered the exact same thing as we did the first time. He got the Green Chicken Curry which he really likes (sorry can't review this personally but it looks good right?!) and I got the 6" hot dog with sweet mustard onions. This was actually an accidental order, I just wanted normal onions because I hate mustard (think I am slightly allergic to it - can one be slightly allergic to something though? My tongue swells a little?) ...but as I couldn't actually see mustard as how I know it, I tried it anyway! I could feel the slight tingles on my tongue but it was so delicious I couldn't leave it! I would definitely order this again, and again, and again! I think the hot dog was just under £5 which is also very reasonable.
I'd really recommend this place (if you ever come across it- there aren't many) if you want 'quality fast food' and to have it in a nice setting.