First of all, Welsh Rarebit is not just cheese on toast, it is cheese on toast with extras such as Worcester sauce and/or brown ale. Here is a recipe
The original spelling was rabbit, the rarebit spelling came later, possibly due to a bit of political correctness (more on that later). Rarebit is the common usage today, but rabbit is still widely used, and many will argue that rabbit is the correct term.
The etymology is from rabbit. One theory is that it was a derogatory term by the English. Whereas the English ate real rabbit meat, the Welsh had to make do with cheese.
Source: Etymology online
[amazon_link asins=’1847716407,1784612456′ template=’ProductCarousel’ store=’yeoglebogle-21′ marketplace=’UK’ link_id=’6a1c19b2-e76c-11e7-af34-9571e4a4fd10′]