This will be to the south of Regent’s Park, but Naroon is my favorite restaurant in London, and we’ve dined there at least once on each of the last several trips. The food is outstanding, it’s Persian (ask them - not Iranian, Persian), and started out as a tiny place on Great Titchfield St., in the Fitzrovia neighborhood. Within a year, they’d become so popular that they moved into a slightly larger place across the street. They’ve now expanded into a small space next door, so not minuscule, but still small enough that making a reservation is wise.
They’ve also opened a second location several blocks west, in the Marylebone neighborhood. I don’t know whether two locations qualifies as being a “chain,” but they’re very personal, and the food is superior. In August this year, we went to both the second location as well as the first one, which is just down the street from our usual B&B. At either location, their entrances are at street level, so neither is quite a hole-in-the-wall, but you still will still have a fantastic meal, and neither is on a completely beaten path.
Still African, but not Moroccan nor Middle Eastern, there’s another notable, new Restaurant a few blocks south of the original Naroon, called Chisuru. Although it’s not super posh, and doesn’t present itself as a usual Michelin-star place, it was awarded a Michelin star right after opening on Great Titchfield Street. The Star is for the quality of the Nigerian dishes, and you won’t get little artistic bites arranged exquisitely on the plate, but will get extraordinary spice flavors. Prices are also much less expensive than at a typical 1-Star Michelin Restaurant in London, and lunch is cheaper than dinner.
One last suggestion, back in Marylebone, is Ishtar. For Turkish, it’s the best I’ve had this side of Turkey.