Make the coffee rub: Toast the cumin seeds in a small dry skillet over low heat until fragrant, about 2 minutes, making sure to shake the pan frequently. Transfer to a spice grinder and finely grind. Mix the toasted cumin seeds with the ground coffee, 1 tablespoon salt, 1 1/2 tablespoons pepper, the chili powder and cinnamon in a small bowl.
Blot the steaks dry. Brush the meat with a little canola oil. Spread the coffee rub on a baking sheet and roll the steaks in the mixture to coat, using about 1 tablespoon per steak. Cover and refrigerate 1 hour but no longer-otherwise, the meat will begin to cure.
Preheat a grill to medium high. Drizzle a little canola oil on both sides of each steak, then grill 5 to 6 minutes per side for medium rare. Transfer the steaks to a cutting board and let rest 15 minutes before slicing.