Mix together the butter, coriander and a pinch of kosher salt with a wooden spoon or gloved hands until combined. Divide into four mounds, and then shape into pucks and place on wax paper. Freeze for 30 minutes.
Preheat a grill to screaming hot.
Mix the beef and chipotle adobo together with a wooden spoon or gloved hands. Divide into 8 portions. Smash the meat into patties, but make a well in the center to accommodate the frozen butter pucks.
Place 1 frozen butter puck in the well of half of the patties. Place the remaining patties on top and crimp the edges of the 2 patties with a fork or your clean hands. Make sure the seal is tight! Freeze the butter-filled burgers for 10 minutes.
Sprinkle each side with a little salt and black pepper. Brush the grill grates well with oil and place the burgers on the grill. DO NOT SMASH THEM. DO NOT FLIP THEM MORE THAN ONCE. Cook to your desired doneness, 5 to 7 minutes per side. Six minutes per side got me a sweet medium rare.
Top with a little fresh cheese if you like. I don't think condiments of any kind are necessary, but go wild if you want. The butter makes even lean ground beef juicy and marvelous but also keeps the center cool so you run less risk of overcooking.
Serve on the buns.
Recipe courtesy of Justin Warner