Are you ready for the ultimate spice challenge? We made compound butters with Scorpion and Carolina Reaper peppers—two of the hottest on the planet—and tried them on juicy ribeye steaks.

The spiciest food on the planet is the Trinidad Scorpion, a golf-ball-sized pepper cultivatable in most parts of the world "You take a bite. It doesn't seem so bad, and then it builds and it ...