When I was a child, Mother would go to the local deli/butcher shop/bakery on Saturday mornings and buy hard rolls (or some wonderful sour rye bread) and raw ground sirloin; we would eat that for brunch, she called them cannibal burgers (Father liked a slice of raw onion on his).
And you're still living? Goodness sakes ....
Never had steak tartare with a roll - too "exoctic" for me .....
- Ron