1/2 roll of paper towel burger. Not much to look at, I know, but it's all in the technique.
I used prime ground beef and let it and some (by some I mean a lot) of Wagyu tallow (beef fat) sit out to warm up at which time I mixed the tallow into the ground beef. I'm thinking it was a 70/30 burger. Wow does that make a difference! One thing I learned is that you want to compact the burger. The one I made, a full half pound, was more loose which made it a handful on the grill. Lots of fire with fat dripping down. To make this awesome burger:
Buttered brioche bun grilled on both sides
Burger grilled, American cheese
lettuce
tomato
dill pickle
red onion
Russian dressing
Grilling the bun and the burger over very high heat proved the way to go. The fat and the prime beef and the char worked perfectly together. Highly recommend mixing tallow into ground beef. You only live once!