I’ve stayed at that Rubens at the Palace a few times. Nice location.
For a nice English breakfast - in a beautiful space- with enough plain things on the menu, a splurge at The Wolseley on Picadilly.
[London] The Wolseley
Rules will have some plainer food for the plain eater and interesting stuff for everyone else. Again, a splurge.
Fortnum’s has a market café on the mezzanine called Field with very good food (including good plainer food),
https://www.fortnumandmason.com/field-restaurant
as well as a food hall with stalls in the concourse, and a tea room on an upper floor.
J Sheekey for a nicer fish dinner.
The place I liked for fish & chips in Soho closed during the Pandemic. The Golden Hind is often recommended.
The Ivy had a few locations, for breakfast or other lunches. [London] Full English breakfast at The Ivy Soho Brasserie
In Paris, I am out of the loop, but we liked Brasserie Flottes for a Brasserie with decent food and some plain options. https://brasserieflottes.fr/en
In Amsterdam, again, out of the loop. The dishes I like when in Holland and when visiting Dutch restaurants- War fries (fries with peanut sauce, mayo, onions), bitterballen (meatballs), croquetten (beef filled croquettes), pfannkoekken (sp- giant crepes filled with savoury or sweet things). Their baked goods, especially apple things, are very good.
