Go to Sam’s Club and buy yourself a PISMO (peeled, intact, side muscle off beef tenderloin.) Then get online and go to Alton Brown’s spot on the Food Network website. I believe he’s got instructions there for cutting and trimming the PISMO.
Or - You can do what I do and just hack it into huge chunks about 1-1/2 to 2 inches think. You’ll be able to char them on the outside without damaging the good bloddy red stuff in the middle.
Slap a little seasoning on, and grill.
By the way, I usually pay around $65 - $80 for the PISMO and it yields around 5 - 7 dinners for two big eaters, or three of more modest appetite.
That's what I do with London Broil. My Father in law has a butcher who will cut them into huge 4-5lb. behemoths for about $2.50/lb. I freeze them a bit to make them juts a bit stiffer for cutting then cut them across the grain into 1" thick medallions. Marinate them in something light for a few hours in a vac sealed pouch. Grill them at high temp for a VERY short time. They are so tender it is like a slice of heaven.
Other than that, blade steaks do it for me. So much flavor when done right.