Since earlier postings clued me to Lundum's in advance of June UK visit, even though the posters had not dined there recently, here's my report.
If you like Scandinavian treats, this is the place for Sunday brunch (the only meal I tried at Lundum's). At £15.50 a head, it's probably one of the better bargains in Chelsea/South Ken.
You'll pay extra to start the meal with Aquavit and a beer chaser, but by all means partake of this Scandinavian tradition. It makes the herring platter that comes out as a first course ever-more delightful.
After herring, the rest of meal you get yourself from a small buffet at the rear of the restaurant.
As I recall, the fish end of the buffet had both gravalax and smoked salmon, two different shrimps and one or two other items. Various salads/vegetables, plus cheeses. I believe there was also a baked fish dish. All that was missing was Jansson's Temptation.
At the other end of the buffet (and we're only talking maybe four or six feet) were the sliced cold cuts, including Denmark's gift to the world of delicatessen, rollepølse.
I've only had rollepølse in other other location: the US midwestern city of Racine, Wisconsin, which at one time boasted a Danish population second only to Copenhagen. Rollepølse is meat (frequently lamb, but I've also seen with made of pork and various combinations of lamb, pork and beef/veal) which has been brined (corned) then rolled with herbs/spices and pressed. Incredible stuff!
Dessert was pleasant enough, though not exceptional. It's probably a good thing they didn't offer kringle, the ultimate Danish pastry.
If you don't like cured/pickled things, especially seafood, you probably would not enjoy Lundum's as much as someone who does. But if you're into herring and other precious gifts from the sea, definitely make a reservation for Sunday brunch (which is served only from about noon until 3 p.m.).
Lundum's is located at 119 Old Brompton Road, SW7. The telephone number is 020 7373 7774.