Cut lengthwise down the center of each pork tenderloin, without cutting all the way through, then open each tenderloin like a book.
In a bowl, combine the chopped garlic, the cumin, oregano, coffee and 1 tablespoon salt. Rub the mixture on the pork. Transfer to a baking dish, cover with plastic wrap and refrigerate for at least 1 hour or up to 24 hours.
Heat a large skillet over medium-high heat. Add the tomatillos and chile and cook, stirring occasionally, until the tomatillos are softened, about 8 minutes. Let cool.
Using a food processor, mix the tomatillo mixture, remaining clove garlic and the cilantro until almost smooth; season with salt.
Preheat the broiler. Brush the pork with the oil. Broil for 5 minutes on each side. Cover with foil and let rest for 10 minutes, then slice on an angle across the grain. Serve with the tomatillo salsa.