Has anyone ever grilled a fillet steak in a toaster?
Not a fillet steak no, but I have cooked veggie burgers in a toaster and it worked really rather well. For a medium rare steak I’d imagine it would need about the second from highest setting, but keep an eye on it. Under-estimate rather than over-estimate cooking time and strength, as you can always put it back in for longer, but you can’t de-cook it! Cleaning is fairly easy providing you have a removable crumb tray as any fat will drip onto that and then easily cleaned. However, your toaster will probably still smell slightly of charred flesh for the next few rounds of toast!