Place steaks on a sheet pan and bring to room temperature an hour before preparing them. Season them on both sides with salt and pepper, then rub oil lightly all over steaks to coat evenly.
Preheat the grill at least 15 minutes before grilling. Grill temperature should be at 500°F. Place steaks down on grill and immediately close lid and let the steaks cook for 3-4 minutes without disturbing it. Flip the steak using tongs and grill for another 3-4 minutes for a perfectly medium-rare steak (130-135°F.). Adjust the cooking time according to your preferred level of doneness. Remove from the grill and let them rest for 10 minutes.
While the steaks are resting, make the vinaigrette. Whisk the whole grain mustard, balsamic vinegar, garlic paste, honey, salt, black pepper, and olive oil. Set aside.
To assemble the salad, thinly slice the steaks. Next, place greens in a bowl or platter. Top with sliced steak pieces, tomatoes, avocado, red onions, raw corn, fresh basil, and blue cheese. Drizzle the dressing over the salad and finish with flaky salt. Enjoy!
