Combine the mustard, paprika, chili powder, 2 teaspoons salt and 1/2 teaspoon pepper in a small bowl. Place steaks on a sheet tray and sprinkle all over with the spice mixture. Let sit at room temperature for 2 hours.
Preheat a grill to medium-high heat and place a cast-iron pan on one side of the grill.
Drizzle the corn, jalapenos and onion with olive oil and sprinkle with salt and pepper. Place on grill and grill, flipping frequently, until slightly caramelized and tender, about 12 to 15 minutes total. Let cool slightly, then roughly chop the onion and jalapeno and place in a large bowl. Cut the corn from the cob into the bowl. Add the tomatoes, garlic, cilantro, vinegar, lime juice and a drizzle of olive oil and toss well. Season to taste with salt, pepper and hot sauce. Let sit while the steaks grill.
Drizzle the preheated cast-iron pan with canola oil. Cook the steaks, flipping only once, for about 12 minutes total for medium-rare or until an instant read thermometer registers 120 degrees F. Allow the meat to rest for 5 to 10 minutes before slicing. Slice the meat against the grain to ensure tenderness, and garnish with the salsa.