Catalyst
Vasilis Chamam and Alex Gkikas' Catalyst might be the iconic London breakfast cafe of the 2020s. It roasts its own coffee and does it well; it provides a familiar litany of British cafe fare such as bacon sandwiches, scrambled eggs, and, maybe soon, a black pudding sandwich, but all of these are infused with the tastes and ideals of its founders' history. A coffee sriracha with heat that blooms like water on its filter coffees; a halloumi katsu sando; and that "black pudding sandwich" with hispi cabbage and XO sauce. It feels like an inheritance and evolution to have so many of London's top greasy spoons run by Greeks and Greek-Cypriots.
The Electric Cafe
The choice of carb to establish a buffer between the solids (bacon, sausage, black pudding) and the gloops is the actual make or break for a greasy spoon connoisseur (egg yolk, beans). Because toast is required and so does not count, the customary options are chips (for lunch and children), hash browns (for Americans and children), and bubble tea (correct). The aficionado's choice is Bubble, and those who subscribe would travel a long distance for a breakfast centered on it, possibly to Tulse Hill.
More about Electric
Electric has been open since 1932 and, like the other classic London cafes Pellicci, Regency, and Alpinos, is owned by a foreigner, in this case Stavros Tsoukkas, whose Greek-Cypriot family has owned the establishment since 1978. The bubble here has a hint of the Mediterranean, powerfully herby with large enough bits of Savoy cabbage to keep scurvy at bay for a day or two, all molded into a giant soft patty fried to a sear on both sides that cuts through the oil and fat like a strong cup of tea.