You know, for a moment I thought the thread title meant:
If you only had one bottle of beer during quarentine, what would it be?
If that were the case I'd have gone one of the bottles below.
1,5 liter Champagne
3 liter Jéroboam
6 liter Méthusalem
One of the first brews I ever made was a Brewferm stout kit. This site actually recommended to add a couple of Weetabix to the FV for mouthfeel and a bit of extra alcohol, if I remember correctly.
So in my opinion it is perfectly reasonable to mix (some) breakfastcereal and beerbrewing.