Wow. Is that butter in the first shot? Or cheese?
Butter.
I followed the recipes loosely. I had closer to 3lbs of meat, so you'd adjust the recipe accordingly. Here it is:
*1 1/2 pounds sirloin steak tips, trimmed and cut into 1/2-inch chunks
*4 tablespoons unsalted butter, cut into 1/4-inch pieces
*Place beef chunks and butter on large plate in single layer. Freeze until meat is very firm and starting to harden around edges but still pliable, about 35 minutes.
*Place one-quarter of meat and one-quarter of butter cubes in food processor and pulse until finely ground into pieces size of rice grains (about 1/32 inch),
*Sprinkle 3/4 teaspoon salt and one teaspoon pepper and over meat and gently toss with fork to combine.
*Divide meat into four portions. Working with one portion at a time, lightly toss from hand to hand to form ball, then gently flatten into 3/4-inch-thick patty. Press center of patties down with your fingertips to create 1/4-inch-deep depression.
*Transfer patties to platter and freeze for 30 to 45 minutes. This step helps ensure the patties stay together.
*Grill!