Let’s clear something up straight away. Rarebit is pronounced rabbit. If you ask for a “Welsh Rarebit” in the UK, you will be met with, at best, a wry smile.
I grew up on the stuff. In fact, if memory serves, this was the first supper I cooked alone.
You can add a whole range of toppings (tomatoes, bacon, ham). Go crazy.
Nostalgia demands I have mine with a glass of milk (whole fat of course) and, following, two Digestive biscuits.