While it’s unlikely anyone visits Terminal 5 for the sheer fun of it, La Belle Époque could well convince some to add an extra hour or so to their travel itinerary. Softly lit booths and rich violet fabrics make it an oasis of calm in the hustle and bustle, while the cooking puts other airport restaurants to shame. Start with pan-fried scallops with smoked pork belly on celeriac purée with artichoke crisp, follow with roast venison fillet with root vegetable remoulade and marinated pear, and finish with a chocolate and kumquat mousse with elderflower and fennel. If three courses before a flight feels a bit excessive, classic afternoon tea is also on offer. While not quite adding Heathrow to the destination dining map, it certainly qualifies as an upside to any delays.