Ibooked Café François in London’s Borough Market for a birthday lunch, despite it having been open for only a few days and knowing precisely nothing about its menu, decor or ambience. This says much about my fondness for its predecessor, Maison François over in St James’, which has long been near the top of my “dependably fancy” and “classy but not pompous” lists. If Maison François is a grande dame living on an exclusive street and serving oeuf en gelée and côtelette de porc, then Café François is her giddier, multi-floored petite fille, who lives in a permanently hectic tourist thoroughfare and serves crisp frogs’ legs, croque monsieur and three types of eclair. If you’ve experienced British secondary school French lessons without coming across the words “croque monsieur” (AKA a melted cheese and ham sandwich), something has gone awry. Café François’ croque mixture, however, oozes from a hot, fresh flatbread, which also come topped with moules marinière or lamb merguez. As for those frogs’ legs, well, they come battered and deep-fried and served with sauce ravigote, which is essentially tartare sauce with added dijon mustard, though maybe say that quietly, because the French are very precious about their sauces. If you’re currently considering those frogs’ legs and quietly hoping that their “frogginess” is fudged in the presentation, stop now: these legs come in attached pairs, splayed and inviting you to feast upon their bottoms. Café François has taken over one of the largest, most easy-to-find spots on Stoney Street, in a brick behemoth of a building that was once a Paul Smith store. Look for the large, glowing signage and the outdoor eating area on a small terrace, which may not be much fun in October, but was still rammed with diners, many of them wearing hats. Café François is certainly less formal than its mothership; there are no tablecloths and no dessert trolley, unlike over in Piccadilly, although here you will be invited to visit the glass-fronted dessert kiosk where you can lasciviously covet the Paris-Brests and other ornate patisserie. While Maison François is more of an occasion destination, Café François has about it a real rolling, all-day-canteen feel, with added finesse. Start at 7am with pain Suisse and ristretto, then, from 11am, have a bowl of escargots and a gimlet for brunch. At lunch proper and dinner, there are sharing platters of lobster, whole roast chicken or prime rib to eat with something off the international wine list. Café François is not a Café Rouge or a Côte brasserie – the fabulous tiling in the loos tells you that from the off – but it could well turn into Borough Market’s most useful rendezvous point. We began with a round of fat anchovies on brioche, spread with a half-inch-thick smear of herby, pistachio-coloured Café de Paris butter, and a mound of fresh celeriac rémoulade, which may be coleslaw with delusions of grandeur, but I love it nonetheless, especially here, where the earthy, knobbly celeriac meets the bitter joy of a very mustardy rémoulade dressing and a garnish of caperberries. Those frogs’ legs were exactly, if not more than, what one might expect from this rather unlovable dish, and my companion ate three pairs of them while looking like a Roald Dahl-esque baddie as he devoured each succulent thigh. For mains, we tried a huge portion of herby steak tartare, which sadly wasn’t chopped tableside, but was elegant nevertheless. In the vadouvan monkfish, meanwhile, I may well have met a new dining downfall. Why even bother to cook at home when Café François is dishing up such large slabs of well-judged white fish in a thick, deeply flavoured curry sauce, and topping it all off with fat mussels? And good luck slurping those mussels from their shells without showering yourself in orange goo. I failed miserably, and the resultant dry-cleaning bill was all my own fault. As an all-day canteen that caters to the world and its dog from the nearby market, Café François is far better than it really needs to be, but this team are proud and diligent types, and far too good to allow their new place to be rubbish. After no little drooling over and pointing at the cakes, we ordered a gloriously pink slice of raspberry gateau and a glossy, hazelnut cream-filled Paris-Brest to share over pots of earl grey and gossip. This is less a casual cafe than a new London landmark. You go and brave the bedlam of Borough Market, if you like, but I’ll meet you at Café François. I’ll be on the first floor, with my onion soup gratinée and hiding behind a copy of Paris Match. Cafe François 14-16 Stoney Street, London SE1, 020-3988 5770. Open all week, Mon-Fri 7am-10pm (last orders), Sat 9am-10pm (last orders), Sun 9am-5.30pm. From about £40 a head à la carte, plus drinks and service